An expert for the U.S. Justice Department described for a jury in a terror trial how Islamic State targets American troops and reaches new recruits.

Terrorism expert Evan Kohlmann testified Tuesday in the trial of a man accused of orchestrating a thwarted shooting attack on an anti-Islam event in Texas last year.

Two friends of defendant Abdul Malik Abdul Kareem brought semiautomatic rifles to shoot up the event but were killed by a police officer.

The two associates had the name of a U.S. military member written on a notebook found in their apartment.

Kohlmann said Islamic State issued a list of 100 military members including photos and their addresses in an effort to wage war with "soldiers of the enemy."