* Gang on motorbikes guns down soldiers
* Incident comes amid frosty bilateral ties
CARACAS, Nov 3 Gunmen have killed two Venezuelan soldiers near the border with Colombia in the latest incident fueling tensions between the Andean neighbors, Caracas said on Tuesday.
A gang of four men on motorbikes ambushed the two soldiers at a checkpoint in Venezuela's western state of Tachira where Colombian rebels, paramilitary militia on both sides and drug-trafficking groups all operate.
Local army head Franklin Marquez said the killing of the soldiers, both shot in the back, could be vengeance for a recent crackdown on criminal activities in the area.
"Sadly, our two men were brutally murdered by groups operating in the frontier zone, trying to spread fear and create an atmosphere of insecurity," he told state media.
Media in Tachira said the border was briefly closed in the area after the shooting on Monday.
One man was arrested, authorities said.
The killings of the soldiers was the latest in a string of incidents on the border, including arrests on both sides, and the discovery of 10 corpses of men whom Venezuela said were mainly Colombian paramilitaries.
In a major diplomatic spat, Caracas is holding three men -- two Colombians and one Venezuelan -- charged with spying for Bogota. The case has worsened already dire relations between Venezuela's socialist President Hugo Chavez and U.S. ally President Alvaro Uribe of Colombia.
(Writing by Andrew Cawthorne, editing by Vicki Allen)