ABUJA, Jan. 26 -- Local and foreign workers were injured during attack by unknown gunmen in the northwest Kaduna State, local police authorities said here on Sunday.

Some Chinese nationals were among the injured victims of the attack at a local construction site, said Olufemi Adenaike, Kaduna State police chief.

The workers were at their duty post, supervising a rail rehabilitation project when the gunmen struck, Adenaike said.

The reason of the attack is still unknown, but eyewitnesses said the gunmen ambushed the workers and shot directly at them.

No death was recorded in the incident, the witness said.