Ammon News - BOGOTA (Reuters) - Colombian leftist guerrillas exploded bombs strapped to two donkeys, killing two workers who were clearing illicit drug crops and wounding six soldiers, police said on Friday.

The attack, near Colombia's frontier with Venezuela, came during an operation to eradicate coca leaves used to make cocaine that is shipped by smugglers to the streets of Europe and the United States.

"Two people were killed and six soldiers were wounded," Police Gen. Orlando Pineda told reporters. The donkeys also died in the blast.

Driven back by President Alvaro Uribe's hardline security campaign, Colombia's FARC guerrillas often use ambushes, home-made landmines and other devices to attack soldiers in their four-decade-long insurgency.

The FARC, once a strong peasant army, has been battered by the deaths of top commanders and a flow of desertions that has sapped its ranks. The rebels have little political support and resort to kidnapping and cocaine trafficking.

In 1996, the FARC used a donkey strapped with dynamite to attack a police post, killing 11 officers, and in 2003 blew up a horse carrying explosives in a blast that killed eight.

Eradicators of coca shrubs are common targets for armed groups looking to protect their drug assets. Violence from Colombia's war has ebbed, but the country remains the world's top cocaine supplier.