Tensions have recently flared over a Colombian military deal with the US
Colombia has accused neighbouring Venezuela of blowing up two pedestrian bridges on its shared border.
Colombian Defence Minister Gabriel Silva said eyewitnesses had seen men who appeared to be from the Venezuelan army blow up the bridges with dynamite.
He described the incident, on the border of Colombia's Norte de Santander region, as violating international law.
A Venezuelan official was quoted as saying that the army had blown up an illegal, improvised bridge.
It was the latest in a series of incidents to cause tension between the two neighbours.
"Uniformed men, apparently from the Venezuelan army, arrived in trucks on the Venezuelan side at two pedestrian bridges that link communities on both sides... and then proceeded to dynamite them," Mr Silva said.
But Alexis Balza, frontier director for Tachira State governor's office, was quoted by Reuters news agency as saying an illegal bridge had been removed.
"The Venezuelan army took down a sort of walkway, put up by the people who pass from Venezuela to Colombia," he said.
Tensions have recently focussed on Colombia's decision to allow the US full access to its military bases.
Venezuela has accused the United States of planning attacks on its territory through the new military agreement - though Bogota says the pact is aimed at fighting drug-traffickers and Marxist rebels within Colombia's own borders.
Earlier this month, Venezuelan President Hugo Chavez urged his armed forces to be prepared for possible war.