YEREVAN: Three employees of a UK-based demining group died in a landmine explosion in the breakaway region of Nagorny Karabakh on Thursday, the organisation and separatist authorities said.
Karabakh is one of the most heavily mined regions in the former Soviet Union.
Mines were laid by Azerbaijani and Armenian forces during a bloody conflict over the rebel region in the early 1990s.
Three local employees of the UK-based demining group, the HALO Trust, were killed and two injured by "the accidental detonation of an anti-tank landmine" in Karabakh earlier Thursday, the organisation said.
"The staff members were in a vehicle conducting survey duties at the 0time," the group said in a statement.
"The injured have been taken to hospital and HALO is contacting the families of those killed."
The rebel region's presidential spokesman, David Babayan, confirmed the incident to AFP.
Azerbaijan and Armenia have been locked in a bitter dispute over the rebel region, with frequent exchanges of fire along Karabakh's volatile frontline.
The international community still views the Armenian-controlled region as part of Azerbaijan and no country has recognised it as an independent nation.
UK-based HALO Trust is the world's largest humanitarian mine clearance organisation.
The demining agency says it has been clearing landmines and cluster munitions in Nagorny Karabakh since 2000 and has already cleared 90 percent of the territory's minefields.
Energy-rich Azerbaijan, whose military spending exceeds Armenia's entire state budget, has repeatedly threatened to take back the breakaway region by force.
Moscow-allied Armenia has vowed to crush any military offensive.