An Ecuadorian soldier and five Colombian irregulars died Thursday in an armed clash on the northern border in the province of Sucumbios, officials in Quito said.

Two other Colombians were captured, the head of Ecuador's Armed Forces Joint Command, Gen. Leonardo Barreiro, said.

The fighting began about 5:45 a.m., after the Ecuadorian troops patrolling the border zone discovered the armed intruders and asked them to turn themselves in voluntarily.

The response of the irregulars, however, was to open fire "with large caliber weapons," forcing the Ecuadorian troops to respond in self-defense, Barreiro told a press conference.

"We need a greater presence and care by the Colombian government on its border so that there are no incursions by armed irregular forces into our territory," Ecuadorian Foreign Minister Ricardo Patiño said at the same session with reporters.

"We don't know what the group is that was there on this occasion ... It's not important to us which it was, we will be absolutely implacable in defending our territorial sovereignty and in defending our soldiers and civilians, too," he said.

Various armed factions, including leftist guerrillas, right-wing paramilitaries and criminal gangs, operate in southern Colombia.

Participating in the operation in Sucumbios were 60 men belonging to special units of the Ecuadorian army, supported by two helicopters, Barreiro said. EFE