(CNN) -- Seven tourists in Thailand were missing Monday after a ferry sank about 12 miles from shore, authorities reported.
The missing include two Swiss nationals, two Australians, one Japanese, one German and one Thai, the Thai News Agency.
The tourist boat, the Choke Somboon 19, left the Similian Islands Sunday night. It was carrying 30 passengers bound for Phuket -- an area popular with tourists from around the world -- when it capsized during a heavy storm.
Marine police rescue crews and a navy helicopters were still searching for the seven in the Andaman Sea, the Thai News Agency reported.
Survivors included 15 international tourists and eight Thais, who were picked up by a rescue fishing boat Monday morning.
The boat operator, Chatri Leechauy, told police the boat capsized because of the heavy rains and wind, the news agency said.