Guests aboard Princess Cruises’ Island Princess were called to their staterooms for a full headcount after a man overboard alarm was reported while the ship was sailing in the Pacific off Mexico, according to passenger posts on social media.

Jim X Skamarakas, who posted updates online, said the ship came to a complete stop and passengers were instructed to return to their cabins while the situation was investigated. “We are dead stop… Everyone to your staterooms for full muster… Man overboard called 1/2 ago,” he wrote.

Alarm reportedly triggered by passenger

In a follow-up, Skamarakas said the initial alarm was prompted after a passenger spoke to a crew member, raising concerns because of how dark it was outside and suggesting someone may have gone over the side. He later reported that the captain informed guests the report originated from that passenger statement, and that the ship’s team initiated procedures to verify the situation.

As part of the response, passengers were asked to remain in their cabins so the crew could complete a headcount, a step commonly used to quickly confirm whether anyone is missing during an overboard alert.