DUSHANBE, February 13, 2012, Asia-Plus -- A transport helicopter has crashed in southern Afghanistan, killing all four people onboard, Radio Liberty reports.

The incident reportedly occurred on February 11 in Zabul Province.

Deputy Provincial Governor Mohammad Jon Rasolyar told RFE/RL that the four dead -- three men and one woman -- were citizens from Tajikistan who were working for Supreme Food, a logistics company under contract to NATO.

He said the helicopter crashed due to bad weather and a "technical problem."

Last year, two Tajik pilots of the Pamir Air company died in a plane crash in Afghanistan.