Bogota has lodged a formal protest with Caracas after five Venezuelan soldiers crossed into Colombia, a foreign ministry official here said yesterday.

The border incident, which nearly caused a riot, occurred Sunday near the Colombian city of Cucuta.

After the soldiers crossed the border, a crowd formed and blocked their passage until police officers arrived and escorted them to immigration authorities, the official said.

They were returned to Venezuela the same day.

“On the same Sunday, a call was made to the ambassador of Venezuela in Colombia (Ivan Rincon), rejecting what happened at the border,” the official told AFP.

“The protest was made official Monday when the Foreign Ministry sent a note of protest to the Venezuelan government.”

Tensions have risen since August when Venezuela announced it would close the border at night as part of a crackdown on smuggling.

Food, fuel and commodities bought at subsidised prices in Venezuela are sometimes smuggled into Colombia and resold.

The contraband trade has exacerbated shortages already hurting the Venezuelan economy, which is reeling from a hard currency crunch and inflation rates of more than 60%.

Venezuela has suffered its ongoing economic woes despite having the world’s largest oil reserves.

Colombia’s two top rebel groups, the ELN and the FARC, will hold separate peace talks with the government, the ELN said Monday, as the sides aim to end decades of conflict.

The National Liberation Army (ELN), said its negotiations will be held parallel to the ongoing talks between the government and the leftist Revolutionary Armed Forces of Colombia (FARC).

“Our slogan is to have two processes with a single goal,” the ELN said in a statement.

The ELN and the government have been in preliminary talks in recent months, which the rebels leader, Nicolas Rodriguez Bautista, nicknamed “Gabino”, said on Sunday had been constructive.

The government has been negotiating with the Revolutionary Armed Forces of Colombia, or the FARC, since November 2012, and has reached agreements on three of the six items on their agenda.

Meanwhile, Colombia said Monday it received a $100mn loan from the German Development Bank to “fund projects for prevention, protection, support and redress for victims” in the post-conflict nation.

The ELN, believed to have some 2,500 fighters, has been active for 48 years, although it has often been overshadowed by the much larger FARC group.

Five decades of fighting between government troops and various guerrilla groups conflict have killed 220,000 people and caused more than 5mn to flee their homes.

Colombian President Juan Manuel Santos has made peace deals with the rebel groups his top political priority.

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