Three people died after a catamaran flipped over on the Caloosahatchee River in Florida on Saturday, authorities reported.

The accident occurred around 4 p.m. near the Cape Coral Yacht Club, with four people aboard at the time.

Three victims were recovered on Saturday, two of whom were pronounced dead, while the third was hospitalized in critical condition.

On Sunday, a fourth victim, a 60-year-old who had been missing, was found dead by the U.S. Coast Guard, ABC News has reported.

The cause of the accident is under investigation, and the victims’ identities have not been released.