GEORGETOWN (Reuters) - In an attempt to thwart “incursion and invasion,” Guyana set up two army bases this week on its jungle frontier with ailing Venezuela, following similar moves by larger neighbors Colombia and Brazil.

Venezuelan soldiers are entering Guyanese territory in search of food, while civilians are seeking medical attention and selling drugs and whatever else they can, according to authorities in the tiny former British colony on the northeastern shoulder of South America.

Brazil and Colombia tightened their borders with Venezuela early this month, as they grapple with a mounting influx of hundreds of thousands of desperate migrants fleeing a worsening economic and social crisis.

Colombia imposed stricter migratory controls and deployed security personnel while Brazil deployed more troops and started relocating tens of thousands of Venezuelan refugees.

Guyana’s 500-mile (800-km) border with Venezuela is mostly impenetrable jungle. Venezuela claims some two-thirds of Guyana, a dispute recently revived after an oil discovery off Guyana’s shores.

President David Granger visited the border village of Kaikan on Wednesday saying it was a “front line” against any attempts at incursion and invasion.

“Frontier communities are guardians of Guyana’s territorial integrity and national security. They are our first line of defense,” said Granger in the small indigenous village.

“TERRORIZING ENCOUNTERS”

The army bases were set up in regions close to the border where residents have complained of “terrorizing encounters” with a notorious gang from Venezuela known as the Syndicatos, the government said in a statement.

One is in Kaikan and another was set up last week in Whitewater, another village, after the Warrau people there reported a large influx of Venezuelans, including military personnel, seeking medical services and trading.

“They come in metal boats and they bring whatever they have to sell - everything from fruits and vegetables to live cattle and plucked chicken,” said Brentnol Ashley, the chairman for Barima-Waini, one of the regions closest to the border, said in an interview.

“In Whitewater, we found Venezuelan soldiers in Guyanese territory in search of food.”

Venezuela is undergoing a major economic and social crisis. The minimum wage has fallen in value to the equivalent of a dollar or two per month amid soaring hyperinflation and shortages of basic goods.

President Nicolas Maduro is seeking re-election on April 22 and is likely to win it given that the country’s opposition has boycotted the vote, describing it as fraudulent and illegitimate.

Venezuelan authorities did not respond to a request for comment.