(Updates with new information)
CARACAS, Jan 4 (Reuters) - A plane carrying 14 people, including eight Italians and one Swiss passenger, crashed into the sea close to a group of Venezuelan islands on Friday and had not yet been found, officials said.
Air rescue and civil protection officials said rescue workers in speed boats and helicopters were still searching for the twin-engine aircraft nearly 10 hours after it went down.
The officials said the pilot reported engine problems just before contact was lost with the Czech-made 19-seat LET L-410.
The plane was flying to the Los Roques archipelago from Caracas but reported engine trouble and never arrived at its destination, an air rescue worker said.
Rain and strong waves have "made the search for the plane more difficult," Gen. Antonio Rivero, who heads Venezuela’s civil protection agency, said in an interview with a local television network.
Rivero said earlier that four additional passengers boarded the plane at the last minute, taking the total to 18 on board, but civil protection said later that information was incorrect.
A spokesman at the Italian Foreign Ministry said eight of the people on board the plane were Italians. He gave no further details.
Civil protection said the plane, operated by Venezuela-based airline Transaven, fell into the sea about 24 miles (39 km) from Los Roques on Friday morning. The agency said in an evening press release that one of the passengers on board was Swiss, after having earlier identified that passenger as American.
The nonprofit Aviation Safety Network reported on its Web site that in 2005 a Transaven-operated aircraft made an emergency landing after taking off from Caracas for Los Roques.
In 2002, another Transaven plane made an emergency landing in the sea while flying to the same islands, according to Venezuelan media. Thirteen people on board were uninjured.
Los Roques is a national park off the coast of Venezuela, renowned for white sand beaches and crystalline water popular with European and U.S. tourists. (Reporting by Frank Jack Daniel and Brian Ellsworth; Editing by Peter Cooney)