Arabic-speaking men carrying guns and grenades hijacked an Air France jetliner and forced it to land in Geneva and Sicily and then flew to Syria where they stopped in Damascus to refuel, officials said.

The hijackers diverted the jet on a Vienna-to-Paris flight. After they forced it to Geneva, they released 37 passengers, The Associated Press reported. The plane also was refueled there.

When it left, officials said it was en route to Athens, but Greece refused to let it land. Officials then reported that the plane was believed to be heading for Libya, where it apparently also was denied landing permission.

The pilot then radioed that the plane was low on fuel, and he was allowed to land at the Catania, Sicily, airport. The jet was refueled, and 55 passengers were released.

Several hours after the jet arrived, an official told reporters, "They said they would start killing people if we don't give them fuel."

At least 21 people, including crew members and three or four hijackers, remained on board when the Boeing 727 took off for Damascus, Catania airport officials said.

Officials said the hijackers' identities were unknown.

Guy Fontanet, a senior Geneva judge who conducted talks at the airport there, said one hijacker stuck a gun through a cockpit window and fired one shot while the plane was on the ground in Geneva, surrounded by police and troops. The shot was not returned and no one was injured. At one point in the negotiations, the hijackers threatened to blow up the plane if the Swiss refused to refuel it, officials at the airport said.

The motive for the hijacking was not known, Fontanet said. He said there was "absolutely no connection" between the hijacking and the U.N. conference on Palestine starting Monday in Geneva.