TUNIS, Tunisia (AP) — More than 30 people have been summoned to face trial over the Tunisia's deadliest attack in a Mediterranean resort.

The trial is scheduled to reopen on Tuesday in Tunis, more than 3-1/2 years after the attack on the Imperial Hotel in the beach resort of Sousse left 38 people dead, mostly British tourists.

The attacker, a Tunisian student who trained with Libyan militants, was killed by police. The Islamic State group claimed responsibility for the attack.

Among the accused, 14 have been summoned even though they are not currently being held in custody and it's unclear whether they will turn up for the trial. Six others are security agents accused of failing to prevent or stop the attack. 

The trial has been postponed several times at the lawyers' request.