A 4-year-old boy is in critical condition after a near-drowning accident on the Royal Caribbean’s Oasis of the Seas on Saturday.

The child wandered away from his mother, who alerted the ship’s authorities, triggering a frantic search about an hour after the ship departed Port Everglades. A guest spotted him underwater in a wave pool and pulled him from the water.

“The child was submerged, swept under the water and was approximately in the water for five to 10 minutes,” said Broward Sheriff Fire Rescue spokesperson Mike Jachles.

Bystanders attempted to resuscitate the boy until the ship’s medical staff arrived, took over CPR and transported him to the infirmary, where pulse was restored.

The Oasis of the Seas returned to port that evening, and the boy was taken to a Fort Lauderdale hospital. His condition was listed as critical.

The child, identified by authorities as Ascanio Azzia of Italy, was on the trip aboard the 5,400-passenger Oasis of the Seas along with his parents and a sibling. Investigators said no foul play was suspected in the incident.

Most cruise ships do not have lifeguards on board, including Royal Caribbean. According to company spokeswoman, signs are posted that warn passengers to swim at your own risk.

Despite the signage, there have been several drowning and near-drowning incidents on cruise ships in recent years.

In February 2014, a 4-year-old boy drowned and his 6-year-old brother nearly drowned aboard the Norwegian vessel Breakaway, which was embarking from New York to the Bahamas. In October 2013, a 6-year-old drowned in a pool on board the Carnival cruise ship Victory. In March 2013, a 4-year-old boy nearly drowned aboard a Disney Fantasy cruise ship.

Cruise ship injury lawyers have expressed many concerns about passenger and crewmember safety aboard these vessels. Those who have been injured or fallen ill on a cruise can get legal assistance by contacting Houston-based personal injury law firm Schechter, Shaffer & Harris, L.L.P., Accident & Injury Lawyers.