Gunmen in Nigeria’s oil-rich Rivers state kidnapped two Lebanese workers helping to build a road, a police spokesman reportedly told Reuters on Sunday.

The workers were abducted on Friday from a site in the Andoni local government area, Rivers state police spokesman Nnamdi Omoni said.

“Some people have been invited for questioning and we hope by the end of today we may close in on the main targets,” Omoni said.

Kidnappings in the oil-producing Delta region where Rivers state sits are not uncommon. In April, gunman abducted two foreign workers from an oil rig, prompting state police to step up security in the area.