Tanzania's government and a transport group say an armed group operating in eastern Congo has seized six Tanzanian and four Kenyan truck drivers and is seeking ransom.

Tanzania's foreign ministry said in a statement Thursday that it is working with Congo's government to secure the release of the Tanzanians.

Angelina Ngalula, who leads the Tanzania Truck Owners Association, says an armed group blocked 12 cargo trucks carrying cement between Tanzania and Congo on Wednesday, setting four trucks ablaze and seizing the drivers. Two of the 12 drivers escaped.

Ngalula says four of the truckers are from Kenya.

She says the armed group is demanding $4,000 per driver in ransom.

Eastern Congo has a number of armed groups active in a vast and mineral-rich region.