Pirates off the coast of Nigeria have attacked a Turkish cargo ship, kidnapping six crew members in a region which has seen increasing piracy in recent years, a Turkish maritime news agency reports.

The Deniz News Agency said among those abducted were the ship’s mechanical engineer, electrician and navigator.

The ship is owned by Kaptanogul Shipping, which told the news agency that both the kidnapped crew, and those who remained on the ship, were “in good health”.

It was unclear how many crew members were aboard the M/T Puli, which was carrying chemicals, when it was attacked, AFP news agency reports.

A ship tracking agency has been tweeting about it. (BBC)