TUNIS, Tunisia (AP) — Investigators say they are searching for one or more accomplices in the attack on a luxury hotel in the Tunisian resort city of Sousse that killed at least 38 people — some of them sunbathers on the beach.

The Interior Ministry's spokesman said on Sunday that investigators are "sure" the attacker, a 24-year-old student killed in the assault on the Imperial Marhaba Hotel, had help.

Mohammed Ali Aroui told The Associated Press that "we are sure that others helped but did not participate" except indirectly.

He said the father of the attacker, identified as Seifeddine Rezgui, and three roommates in Kairouan where he studied have been detained for questioning.

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