The recently completed trial of four Osama bin Laden associates in U.S. Federal Court in New York City -- the trial began in January 2001 and sentences were handed down in May 2001 -- provides a revealing glimpse into the workings of the Osama bin Laden network, called Al Qaeda or "the base." Four men were tried on charges related to the simultaneous bombings at two American embassies in Africa on August 7, 1998, which killed 224 people and wounded thousands.

Shortly after the embassy bombings, the U.S. government claimed that Osama bin Laden was responsible. They issued a lengthy indictment of bin Laden and many of his associates in the late fall of 1998. According to court documents, the U.S. government had actually been tracking a bin Laden cell operating in Kenya before the bombings and they were able to quickly link these men to the bombings. Several were arrested and brought to the U.S. for trial. Other key operatives escaped and are still at large.

The trial began in U.S. District Court in New York City in January 2001. The evidence presented at the trial paints a detailed picture of the Al Qaeda organization and a history of bin Laden's life and political beliefs.

The four defendants were charged with conspiring in the bombing of two American embassies in East Africa in 1998 and in other acts of terrorism as part of bin Laden's international organization. The indictment outlines a worldwide conspiracy and creates a picture of a sophisticated international terrorism network. All of the defendants pleaded not guilty.

Mohamed Rashed Daoud al-'Owhali, 24, is a Saudi citizen who was a would-be suicide bomber, riding in the truck that took the bomb to the embassy in Nairobi. He signed a detailed confession and provided U.S. authorities with keys that fit into a padlock on the rear of the bomb-laden truck. He apparently ran away from the bomb site and was treated for injuries at a nearby hospital where he was arrested. He was eligible to receive the death penalty if convicted.

Outcome: Convicted in May 2001. After a lengthy hearing, the jury decided not to give the death penalty, most likely in order to prevent him from becoming a martyr. He was sentenced to life in prison without parole on October 18, 2001.

Khalfan Khamis Mohamed, 27, is a Tanzanian citizen who rode in the truck that carried the bomb to the embassy in Dar es Salaam. He also rented the house where the bomb was made and helped to build the bomb and load the truck. Mohamed was arrested in Cape Town, South Africa, in October 1999 and also signed a confession. He was eligible to received the death penalty if convicted.

Outcome: Convicted in May 2001. After a lengthy hearing, the jury decided not to give the death penalty, most likely in order to prevent him from becoming a martyr. He was sentenced to life in prison without parole on October 18, 2001.

Mohammed Saddiq Odeh, 35, is a Jordanian citizen who joined Al Qaeda in 1992 and served as a "technical advisor" to the Nairobi bombing cell. He left Kenya just before the bombing and was arrested trying to enter Pakistan with a fake Yemeni passport. He was interrogated by Pakistani officials, and eventually admitted being part of the embassy bombing conspiracy. FRONTLINE obtained a translation of the Pakistani authorities' original notes from his interrogation in which he describes his role in the Kenya bombing.

Odeh was also implicated in the killing of American soldiers in Somalia in 1993.

Outcome: Convicted in May 2001. He was sentenced to life in prison without parole on October 18, 2001.

Wadih El-Hage, 40, is a naturalized American citizen who was born in Lebanon. He has admitted being Osama bin Laden's personal secretary. He was accused of being the key organizer of the Kenya cell and of setting up front companies in Kenya for Al Qaeda. He left Kenya almost a year before the bombings, after being questioned by the FBI in Africa. At the time of the bombings, he was living in Arlington, Texas, with his wife, April, and seven children. El Hage claimed he only worked for bin Laden in legitimate businesses and had no contact with him since 1994. El Hage was charged with conspiracy to murder Americans and could face life in prison.

Outcome: Convicted in May 2001. He was sentenced to life in prison without parole on October 18, 2001.

The U.S. government's case against the bin Laden operatives was based on the testimony of two key witnesses -- Jamal Ahmed Al-Fadl and L'Houssaine Kherchtou. They provided detailed testimony about the structure and inner workings of the international network set up by Osama bin Laden.

Jamal Ahmed Al-Fadl, a Sudanese citizen, was a former member of Al Qaeda who became disillusioned with the organization and stole some money from bin Laden before coming to the American government to provide information in 1996. He was the most important witness for the prosecution during the trial and provided essential details about the structure of Al Qaeda around the world. L'Houssaine Kherchtou, a Moroccan citizen, testified that he wanted to leave Al Qaeda after he was refused $500 to cover the cost of an emergency operation for his wife. He also provided information to the American government, describing the organization as running into money problems during 1994.

Both Al-Fadl and Kherchtou have been placed into the Witness Protection Program.

The American government's understanding of the bin Laden network was also aided by another man who did not testify publicly, but provided key intelligence behind the scenes -- Ali Mohamed, a 48-year-old Egyptian native and former U.S. Army sergeant. He was the first person to plead guilty to charges resulting from the embassy bombings. In October 2000, Mohamed told Judge Leonard Sand of the U.S. District Court in Manhattan that at the request of bin Laden, he had conducted surveillance of U.S., British, and French targets in Nairobi, including the U.S. embassy. He then delivered pictures, diagrams, and a report to bin Laden in Khartoum, Sudan. He said that bin Laden looked at a photograph of the U.S. embassy and pointed to the place where a bomb truck could be driven through. The targets were chosen, Mohamed said, to retaliate against the U.S. intervention in the civil war in Somalia.

Mohamed is a naturalized U.S. citizen who worked as a supply sergeant in Fort Bragg, N.C., from 1986 to 1989, before going to work for bin Laden. He trained Al Qaeda operatives in military techniques and acted as a key adviser in the organization. While Ali Mohamed is cooperating with the U.S. government, he did not testify in the embassy bombing case.

Al-Fadl described Al Qaeda as a group formed by Osama bin Laden after the Soviets pulled out of Afghanistan. Many of the top leaders and members fought in the "jihad" against the Soviets. Al-Fadl was one of the first members to swear the required "bet," or loyalty oath, to join the group. Al-Fadl described the organization with bin Laden at the helm, followed by a council of leaders who help to make decisions. Below that level, he says, are a series of committees who handle religious policy, military training, legitimate business, and even press releases.

The group initially sought to overturn the governments of Saudi Arabia, Egypt, and other Islamic countries whose leaders were not subscribing to radical Islamic rule. In the early 1990s, bin Laden set up the group in the radical Islamic country of Sudan. After the U.S. became involved in Somalia, and put troops into Saudi Arabia, bin Laden turned against the United States. In February 1998, he issued a searing religious declaration asking Muslims around the world to attack U.S. citizens. The African embassies were bombed six months later.

No real evidence was presented at trial as to the actual extent of bin Laden's financial network. He is one of many sons in a very wealthy family, which is originally from Yemen and in charge of most of the construction projects in Saudi Arabia. But testimony provided contradictory evidence about the extent of bin Laden's current wealth.

There was also no direct evidence presented at trial that bin Laden himself ordered the bombings, although the prosecution did establish the links between bin Laden and the four men on trial. They also established through phone records and wire tap transcripts that there was satellite telephone contact between the Nairobi cell and bin Laden himself.

Ali Mohamed confirmed that the larger objective of bin Laden and his association is to attack Western targets in the Middle East, in order to force Western governments to pull out of the region. He also detailed the relationships between bin Laden's organization, Al Qaeda, and other terrorist groups such as the Egyptian Islamic Jihad and the Iranian-backed Hezbollah.

The trial testimony suggested that Al Qaeda establishes "cells" in areas where they are planning attacks, often separating the planning cell from the execution cell. They use low level recruits for administrative tasks not requiring any knowledge of the larger plan.

The Africa cell was managed by a fairly high-ranking member of Al Qaeda, Khaled al Fawwaz, a Saudi dissident who was living in England. He was in constant contact with Osama bin Laden, phone records showed, and was responsible for media contacts for Al Qaeda as well. Al Fawwaz is now in custody in England and awaiting extradition to the United States.

The U.S. attorneys described defendant Wadih El Hage as a leader of the Nairobi cell who had to leave Africa after being interviewed by the U.S. FBI in 1997. The other three defendants appear to be lower level cell members who were all trained at Al Qaeda training camps in Pakistan.

In total, the U.S. government has public indictments against 26 members of bin Laden's international group, Al Qaeda. Of those men, three have pleaded guilty and are cooperating with the U.S. government as witnesses. Four were tried this year. Six are in custody in the U.S. or abroad and are awaiting trial. Thirteen, including bin Laden himself, are fugitives.

The six other bin Laden associates in custody include several high-ranking members of Al Qaeda:

Mamdouh Mahmud Salim, a high-ranking religious leader in Al Qaeda, was arrested in Germany and extradited to the United States. He is scheduled to go on trial this month in New York for stabbing a prison guard while being held in the New York City federal jail.

Khalid Al Fawwaz was arrested in England and has been accused of running bin Laden's public relations office. He has been indicted, and remains in custody in England pending extradition.

Egyptians Adel Abdul Bary and Ibrahim Hussein Abdelhadi Eidaros were also arrested in England and remain in custody pending extradition. According to the criminal complaint against them, the fingerprints of both men were found on faxes of documents related to the East Africa bombings. The complaint also alleges that Eidaros secretly organized a terrorist cell in Afghanistan and has been involved in providing passports for and otherwise assisting fugitive terrorists.

Mohammed al Nalfi is a Sudanese citizen being held in the U.S. facing conspiracy charges for allegedly supporting bin Laden and Al Qaeda when it was based in Khartoum.

Ihab Ali Mohamed is a naturalized U.S. citizen originally from Egypt. He has been held in a U.S. jail for several years, accused of lying to a grand jury about his connections to bin Laden. Evidence at trial indicated that Ali had passed messages for Al Qaeda and had trained to be bin Laden's pilot.