Two crew members participating in the Sydney to Hobart yacht race in Australia are dead after separate accidents at sea, police announced late Thursday.

The men were hit in the head by booms on their yachts in separate episodes, as participants faced challenging weather conditions, the police said.

Two sailors on separate boats have died in boom accidents two hours apart on a storm-ravaged first night of the annual Sydney to Hobart race, adding to the event’s long history of deaths at sea. The Cruising Yacht Club of Australia in Sydney,