The navy is searching for four people who disappeared after an accident involving a recreational vessel that was carrying nine people on the Parana River, Argentine officials said Sunday.

The La Berbena capsized Saturday, tossing its passengers into the river near Ramallo, a town in Buenos Aires province, the Security Ministry said.

Five of the boat’s occupants managed to swim ashore, but four men went missing.

The boat’s occupants were returning from a fishing trip on the Parana River in Buenos Aires and Entre Rios provinces.