A cruise ship passenger from the US has died after developing breathing difficulties while swimming at Horseshoe Bay, police said today.

Ruth Birtwell, 63, of Ashford, Connecticut was in shallow water on Thursday afternoon when she was struck by a wave that knocked her over.

A pre-existing medical condition may have contributed to Ms Birtwell’s breathing trouble, a police spokesman said. She was taken by ambulance to King Edward VII Memorial Hospital but was pronounced dead shortly before 2.00pm

An autopsy is expected.

Police offered condolences to Ms Birtwell’s family and friends.