A hearing expected to reveal new details about a 2009 shooting rampage at Fort Hood Army base in Texas has adjourned without any testimony.
US Army psychiatrist Maj Nidal Hasan is accused of killing 13 comrades and wounding 32 in the 5 November attack.
Victims were to testify at a hearing to determine whether prosecutors have enough evidence to try Maj Hasan.
Maj Hasan's defence team sought a delay until next month. The hearing is expected to resume on Wednesday.
Maj Hasan could face the death penalty if convicted. The attack was the worst ever at a US military base.
Military officials say Maj Hasan, a Virginia-born Muslim of Palestinian descent, opened fire on comrades at Fort Hood's crowded Soldiers Readiness Processing Center, where troops get medical check-ups before deploying abroad.
Paralysed in attack
Relatives have said Maj Hasan, 40, had been harassed over his ethnicity and was unhappy about a possible deployment to Afghanistan. He had worked as a psychiatrist treating troops returning from combat.
The military judge in the case, Col James Pohl, has said he wants to hear from all 32 victims wounded in the attack. The current Article 32 hearing is expected to last three weeks.
Among those expected to testify is Sgt Kimberly Munley, the base police officer injured when she and another officer opened fire on the gunman during the attack.
Maj Hasan was paralysed in the attack and spent months in hospital under armed guard. He has appeared at previous court hearings in Army uniform, in a wheelchair.
Following the attack it emerged Maj Hasan had been in contact with an extremist Yemeni-American cleric in the months before the shootings.