The Colombian navy said a convicted kidnapper who used a toy hand grenade to hijack a Colombian airliner was captured Tuesday morning in a swamp near the international airport of the Caribbean coast city of Cartagena.

No one was injured in the 11-hour hijacking, which began during a morning flight from Medellin to Bogota and ended when the plane landed in Cartagena Monday night. All 128 passengers and the three flight attendants were freed shortly after the Avianca Boeing 727 was commandeered.During the hijacking, a man claiming to have hand grenades forced the plane to fly to Panama and Aruba. He demanded $100,000, saying he was dying of cancer and wanted the money so he could live out his days happily in Cuba.

The aircraft unexpectedly landed in Cartagena after the flight crew persuaded the hijacker that they did not have enough fuel to reach Cuba.

Authorities knew nothing about the change of plans and were caught off guard. As the jet taxied in the darkness toward the Cartagena terminal, the hijacker lowered the rear stairway, jumped out and escaped.

The man was found at dawn Tuesday hiding in a swamp on the edge of the airport, the navy said. He was being examined by doctors.

The navy said the man, Gonzalo Carreno Nieto, used a toy gun four years ago to kidnap an uncle.

Carreno spent nine years in prison after being charged with murder, lawyer Guillermo Garcia said. He eventually was found innocent and set free, but had become emotionally unbalanced in prison and turned to crime and drug abuse, Garcia told the radio network Caracol.

At a news conference in Cartagena, pilot Luis Eduardo Gutierrez said of the hijacker: "He wanted the $100,000 so he could spend the last few days of his life happily. He told us he had nothing to lose and that he would explode a grenade he carried in his hand if we failed to obey his instructions."

The jetliner had left Medellin on a flight to Bogota, Colombia's capital 250 miles southeast.

Shortly after takeoff, passenger Javier Robledo said, the hijacker gave a note to a female flight attendant. Robledo, who was sitting next to the man, said the stewardess led the hijacker to the cockpit.

The passengers and the flight attendants left the plane when it returned to the Medellin airport.

"Our most difficult moments came in Aruba when the hijacker realized he couldn't get the money there, either," said Gutierrez. "I told him that he could probably get it in Cartagena, and he agreed we go there."