Colombia arrests 15 soldiers for peasant killings

BOGOTA, April 29 (Reuters) - Fifteen Colombian soldiers were arrested on suspicion of killing two farmers in 2005 and passing their bodies off as leftist guerrillas killed in battle, prosecutors said on Tuesday.

The arrests were announced as Colombia tries to convince the U.S. Congress to pass a free trade deal and continue military aid despite accusations of illegal executions and other human rights abuses by state security forces.

Another 14 soldiers are wanted in the case of Frank Martinez and Claudio Olmero, who the attorney general says were falsely identified by the army as insurgents killed in action in the northern province of Cesar.

Security forces are often accused but rarely convicted of abuses connected to a 44-year-old war involving Marxist guerrillas, right-wing paramilitaries and other groups funded by Colombia's multibillion-dollar cocaine trade.

"I do not think these 15 arrests would have been made without pressure from the United States," said Lisa Haugaard, head of the Latin America Working Group, a Washington-based human rights organization.

Senate Democrats have held up some military assistance to Colombia based on reports of illegal executions. The army says it is addressing the problem by ordering soldiers to try to capture rather than kill insurgents.

President Alvaro Uribe, the White House's staunchest ally in South America, is popular for his U.S.-backed crackdown on the rebels, which has cut urban crime and helped spark economic growth.

But the military push has been accompanied by claims that soldiers, under pressure from their commanders to show results, have killed innocent peasants and dressed them as guerrillas to pass them off as fighters killed in battle.

"These crimes will end only when soldiers see clearly that they will go to jail in these cases. So the pressure needs to be kept up," Haugaard said.

Human rights groups estimate that nearly 1,000 civilians have been executed by security forces during the president's six-year-old offensive against the Revolutionary Armed Forces of Colombia, or FARC.

Uribe, whose father was killed in a botched FARC kidnapping in the 1980s, is pushing hard for a trade deal. But Democrats in the U.S. Congress say he must do more to safeguard the rights of labor leaders and others targeted by right-wing death squads. (Editing by Kieran Murray)