A British doctor, his wife and two other men have been kidnapped by gunmen in the Niger Delta region.
Police spokesman Andrew Aniamaka said the four were abducted around 2am from a small community
He said the four were involved in preaching and providing free medical services to locals.
Mr Aniamaka says it is believed that militants carried out the kidnapping.
No ransom demand has been made.
Kidnapping for ransom is common in Nigeria.
An Italian priest was kidnapped October 12, though Italy's foreign minister said on Wednesday he has since been freed.