BUCHAREST, Romania (AP) — Romania's foreign ministry says a Romanian engineer abducted in southern Nigeria has been freed.

The ministry did not provide details of the man's release in its statement late Wednesday. It thanked Nigerian authorities and the crisis team the ministry set up to handle the situation.

Armed men attacked a group of foreigners Monday evening at a railway construction site in Agbor in Delta state and kidnapped the man. Nigerian police identified him as Christian Nedelcu, an engineer with Dextron Nigeria Ltd, a construction firm.

Kidnappings of Nigerians and foreigners are common in Nigeria. In the oil-rich southern Niger Delta, they are carried out by ordinary criminals as well as by militants demanding a greater share of oil riches for locals.

Hostages are usually released unharmed after ransom payments.