BOGOTA (Reuters) – Colombia on Wednesday warned its citizens of the dangers of visiting Venezuela after eight Colombians were detained in the neighbouring country on espionage accusations.

“The foreign ministry warns Colombians about the risks of travelling to Venezuela,” the government said in a statement, the latest salvo in a long diplomatic feud between Colombia’s conservative government and Venezuela’s leftist firebrand President Hugo Chavez.

Colombian leader Alvaro Uribe accuses Venezuela of violating the rights of the Colombians arrested in Venezuela in recent weeks for allegedly spying on its ailing energy infrastructure.

The detention followed months of jibes between Uribe, the top US ally in South America, and Chavez, who is wrestling with power shortages that could boost opposition prospects at legislative polls due in September.

Chavez has clamped down on trade with Colombia and accused “counter-revolutionaries” opposed to his socialist government of slashing power cables to worsen the OPEC nation’s electricity crisis, which has forced his administration to ration power in much of the country.

In practice, it could be difficult for many Colombians who work in Venezuela or have family there to refrain from crossing the lengthy border.

Tens of thousands of people move from one side to the other every day.