Updated

The Army psychiatrist on trial for the 2009 shooting rampage at Fort Hood says the deadly attack was provoked by American soldiers being deployed to "engage in an illegal war."

Maj. Nidal Hasan told a military judge on Thursday that the shooting wasn't in the heat of passion. He says jurors shouldn't have the option of convicting him of voluntary manslaughter.

Hasan is accused of killing 13 people and wounding more than 30 others at the Texas Army post in the deadliest mass shooting ever on a U.S. military base. If convicted, he could face the death penalty.

Hasan is acting as his own attorney, and his statements marked one of the rare moments that he's spoken during the 12-day trial.

Jurors were not in the courtroom at the time.