Ousted President Manuel Zelaya was kept from returning to Honduras Sunday because the country's main airport was blocked by the interim government's soldiers and military vehicles.

The pilot of the Venezuelan plane carrying Zelaya said landing at the airport was "totally impossible" and landed the plane in Nicaragua instead.

Zelaya said he vowed to make another effort to return either Monday or Tuesday.

Despite Zelaya's appeal for a peaceful protest, violence broke out at the airport. Security forces fired tear gas at protesters, some of whom were throwing rocks and setting fires.

At least one person has been killed.

Zelaya defiantly demanded the military step down.

"I am the commander of the armed forces, elected by the people, and I ask the armed forces to comply with the order to open the airport so that there is no problem in landing and embracing with my people," Zelaya said from his plane. "Today I feel like I have sufficient spiritual strength, blessed with the blood of Christ, to be able to arrive there and raise the crucifix."

Zelaya has won overwhelming international support since he was exiled to last week to Costa Rica by the military and is being accompanied on his plane by the U.N. General Assembly president.

Other Latin American leaders planned to fly with him but backed out, citing security concerns.

The interim government's foreign minister said the military has been ordered to prevent the president's plane from landing and to block any unidentified aircraft.

"The government of President (Roberto) Micheletti has ordered the armed forces and the police not to allow the entrance of any plane bringing the former leader," Enrique Ortez, told The Associated Press.

Most commercial flights into and out of the Tegucigalpa airport were cancelled and access roads were peppered with police and army checkpoints.

Zelaya, who was kicked out of office a week ago in a military coup, encouraged his supporters to gather at the airport.

"No one can obligate me to turn around. The constitution prohibits expelling Hondurans from the country. I am returning with all of my constitutional guarantees," Zelaya declared from his plane over a Venezuela -based television network.

Thousands of supporters made their way to the airport for the showdown, as police helicopters hovered overhead and riot police stood guard.

"We are going to show up at the Honduras International Airport in Tegucigalpa ... and on Sunday we will be in Tegucigalpa," Zelaya said in an audio message he posted on the Internet.

"I ask all farmers, residents, Indians, young people and all workers' groups, businessmen and friends ... to accompany me on my return to Honduras," he said. "Do not bring weapons. Practice what I have always preached, which is nonviolence. Let them be the ones who use violence, weapons and repression."

"I hold the coup plotters responsible for the lives of each and every person," he said.

At least three other planes, carrying Latin American leaders, members of the Organization of American States and journalists, are tailing Zelaya's plane.

The interim government has said it will arrest Zelaya and put him on trial despite widespread condemnation of the coup.

The military stormed Zelaya's home early last Sunday and put him on an airplane for Costa Rica just as the country was set to vote in a referendum on constitutional reform.

The international community immediately called for Zelaya to be reinstated, a call that went unheeded. In retaliation, the Organization of American States on Saturday suspended Honduras as a member. A few hours earlier, Micheletti had pulled out of the OAS rather than reinstate Zelaya.

Cardinal Oscar Andres Rodriguez pleaded with Zelaya not to antagonize the interim government, saying Saturday that "your return to the country could unleash a bloodbath."

The interim government said it will charge Zelaya for 18 alleged crimes, including treason and failing to implement more than 80 laws that have been approved by Congress since he took office in 2006.