Four men on trial in the bombing of U.S. embassies in Africa were on a mission to kill Americans "merely because they were Americans," a prosecutor said Tuesday in closing arguments.

Assistant U.S. Attorney Kenneth Karas showed jurors in Manhattan federal court a video of the aftermath of the deadly 1998 attack in Nairobi, Kenya. He called the scenes of the bombed-out embassy and smoldering cars "a painful reminder of why we have spent the past 2 months together."

Karas argued the government had proven that the defendants -- identified as followers of exiled Saudi millionaire Osama bin Laden -- guilty of "unspeakable acts."

"We have established the guilt of these defendants in a conspiracy to murder the people of the United States merely because they were Americans," he said.

The defendants are charged with murder conspiracy in the Aug. 7, 1998, bombings of embassies in Nairobi and Dar es Salaam, Tanzania. The attacks left 224 people dead, including 12 Americans.

Prosecutors were expected to use the rest of the week to explain the hundreds of exhibits they had entered into the record since early February. Defense arguments would then follow.

If convicted, Mohamed Rashed Daoud Al-'Owhali, 24, and Khalfan Khamis Mohamed, 27, could face the death penalty. Sadeek Odeh, 35, and Wadih El-Hage, 40, could face life in prison.

None of the four defendants testified before the defense rested its case Monday. U.S. District Judge Leonard Sand questioned three of the four individually to make sure they understood their right to testify, as he did with the fourth defendant several weeks ago.

At trial, prosecutors portrayed the defendants as militant Muslims recruited by bin Laden's terrorist organization to fight a holy war against the United States. Bin Laden -- a fugitive believed to be under the protection of Afghanistan's ruling Taliban militia -- "wanted to export jihad ... to fulfill his dream," Karas said.

Prosecutors alleged that El-Hage led "a secret double life," traveling the globe to raise money for Al Qaeda's terror plots and even shopped for Stinger missiles on the black market.

Odeh, an alleged explosives expert, was accused of being a technical adviser to the terror group. Prosecutors claimed Al-'Owhali personally asked bin Laden for "a mission," and ended up riding in the truck that carried the bomb to the Nairobi embassy.

Mohamed was charged with renting a house that was used as a bomb factory in the Tanzania attack, helping grind the TNT used in the explosion. On the day of the bombing, the defendant "prayed that the bomb went off, and was happy when it did," Karas said.

Defense attorneys have not disputed that El-Hage, an American citizen who last lived in Arlington, Texas, once worked for bin Laden. But they insisted he only was involved in legitimate business ventures.

Defense attorneys have said Mohamed was a mere "pawn" who was unaware of the bomb's intent, called evidence against Odeh inconclusive, and said Al-'Owhali is a devout Muslim who never advocated killing innocent Americans.