Mustafa Kamel Mustafa was emotional on Thursday as he also described losing his hands and an eye. He says he worked as an engineer in 1993 when he assisted in the testing of liquid explosives for the Pakistani military. He says he was given a device that heated up and exploded before he could toss it away.
Mustafa laughed as he recalled hearing rumors his hands were cut off as punishment for crimes.
He later cried while describing the killing of Muslims in Bosnia.
He has denied participating in a 1998 kidnapping in Yemen and trying to organize a jihad training camp in Oregon.