Prosecutors argued that the defendants in the Fort Dix terror plot case used paintball games as training for an attack against the Army training center.

But defense lawyers said that they were just having fun.

The trial of the five foreign-born Muslims accused of plotting to kill U.S. soldiers at the New Jersey military facility reached a milestone Thursday as paid government informant Mahmoud Omar completed 13 days of testimony.

Click here for photos.

Thursday's questioning focused on a tape Omar made during a paintball outing with some of the alleged plotters in February 2007.

At one point, defendant Shain Duka told Omar that paintball is good training, a statement prosecutors say shows the men were preparing for an attack.

But defense lawyers focused on another portion of the transcript in which Duka described the game as being fun.

The five, who were all in their 20s when they were arrested in the spring of 2007, could face life in prison if they're convicted. They are charged with conspiring to kill military personnel and attempted murder. They lived for years in Cherry Hill, N.J., outside of Philadelphia.

No attack was carried out.

Omar has said that he did not speak directly to some of the suspects about attacking Fort Dix.

But one, Mohamad Shnewer, was serious about his intentions to invade, according to Omar.