Twelve beaches in Hong Kong were closed after a large shark was seen near Lamma Island last week.
Anne-Sophie Girard was one of the first people to see the giant fish. She was on a boat at Sham Wan, on Lamma, enjoying a party with her family and friends. But suddenly the boat's captain saw a fin in the water. He quickly told the swimmers to get back on the boat.
'At that moment, we were just really scared. It was quite a big shark,' she said.
It may have been a whale shark, the world's biggest kind of shark. They can grow to over 12 metres long and weigh over 20 tonnes.
But whale sharks only eat plankton, a kind of tiny sea animal. They are not dangerous to people. Anne-Sophie said the shark did not seem aggressive, even though it swam under their boat.
Government officials decided to close 12 beaches, including the busy one at Repulse Bay.