The FBI’s Houston field office is “aware of an incident” that took place around July 23 aboard the Carnival Dream, the agency said.

Passengers on the ship told said they woke up to the sound of sirens at around 3 or 4 a.m. Wednesday, and one heard a request for medical assistance on one of its decks, according to KHOU.

An FBI investigation is underway after an incident on a Carnival Dream cruise ship based out of Galveston, Texas, according to multiple reports. KHOU cites law enforcement sources, who claim there is a "death investigation.