Venezuelan security forces have carried out joint operations with Colombian rebel group the National Liberation Army (ELN) against former members of the FARC rebels who remain armed, advocacy group Human Rights Watch (HRW) said on Monday.
The operations have been carried out along the porous border between the countries, which divides the Colombian province of Arauca from the Venezuelan state of Apure, HRW said in a report.
The Revolutionary Armed Forces of Colombia (FARC) demobilized under a 2016 peace deal with the Colombian government, but some former fighters reject the accord and formed dissident groups Colombian authorities say are involved in drug trafficking and illegal mining.
At least 103 people were killed in Arauca in the first two months of this year amid violence between armed groups, which also forced thousands to flee, the report said. The figure is the highest for Arauca for January and February since at least 2010.
The ELN and dissidents commit murders, forced recruitment of children and displacements, HRW said, adding Venezuelan security forces are sometimes complicit with ELN abuses.
"Armed groups are committing brutal abuses against civilians in the Colombia-Venezuela border area, in some cases with the complicity of Venezuelan security force members, while Colombian authorities haven't done enough to respond," said Tamara Taraciuk Broner, acting Americas director at Human Rights Watch.
"Colombian authorities should urgently ramp up their efforts to protect the population and assist displaced people."
The Venezuelan Information Ministry did not immediately respond to a request for comment.
At least 3,860 people have been internally displaced in Arauca and more than 3,300 have fled Venezuela for Arauca and Vichada, another Colombian province, since combats began, HRW said.
Colombian President Ivan Duque has increased troop presence in Arauca - an oil-producing region - but HRW says the effort has fallen short.
The government in Bogota accuses Venezuela's President Nicolas Maduro of harboring dissidents and the ELN, something Maduro has repeatedly denied.
(Reporting by Luis Jaime Acosta in Bogota; Additional reporting by Vivian Sequera in Caracas; Writing by Julia Symmes Cobb; Editing by Andrea Ricci)
