Gunmen kidnapped a Chinese from his residence in central Nigeria’s Kogi state, police said on Wednesday, vowing to track down the attackers and free the hostage.

“The incident happened in the early hours of Tuesday when armed men stormed the official residential quarters of the Kogi State Water Corporation and abducted a Chinese national,” police spokesman Elvis Aguebor said.

The gunmen shot into the air before fleeing with the hostage, who was a consultant to a government water project, Aguebor added.

The motive for the abduction was not immediately clear.

Kidnapping for ransom is common in Nigeria, particularly in the oil-producing region where dozens of expatriates work and live.