Four children were found unresponsive on a river in the Canadian province of Quebec early Saturday morning and later pronounced dead after a group of 11 people on a fishing trip got caught in the tide, police said.

Four children have died and a man remains missing after 11 people fishing on the shore of the St. Lawrence River in the Canadian province of Quebec were swept away by a tide, police said on Saturday.

The children, all over the age of 10, were found unresponsive early Saturday morning on the shore in the Portneuf-sur-Mer area north of Quebec City. They were taken to a hospital in the region and police later confirmed they were dead.

A spokesperson for the Quebec provincial police said 11 people went missing after leaving by foot for a fishing trip and being caught by the tide. He said emergency responders were called at 2 a.m. on Saturday to Portneuf-sur-Mer.

Six of those 11 people were rescued from the river and five remained missing overnight, the spokesperson said.

A man in his 30s is still missing, according to Quebec provincial police, and a search for him with divers, boats, and helicopters is ongoing.

Quebec provincial police are investigating the circumstances of the incident, the spokesperson said.

The incident occurred in the Côte-Nord region of Canada’s Quebec which covers much of the northern shore of the Saint Lawrence River.