KADUNA, Nigeria (Reuters) - Kidnappers have abducted two Americans and two Canadians in the northern Nigerian state of Kaduna, killing two police officers, a police spokesman said on Wednesday.

Kidnappings are rife in Nigeria, where domestic security is weak, though they overwhelmingly target other Nigerians. However, abductions of foreigners are not uncommon.

The foreigners were ambushed by unknown gunmen on their way from the town of Kafanchan in Kaduna state to the capital Abuja, Mukhtar Aliyu, a spokesman for the Kaduna state police, said by telephone.

Kafanchan is about 3-1/2 hours’ drive northeast of Abuja.

“The two police escorts attached to them engaged the kidnappers in a fierce gun battle, which resulted in the unfortunate death of the two police officers,” Aliyu said.

The United States embassy in Nigeria declined to comment.

Global Affairs Canada is aware of the reports of the kidnapping of two Canadian citizens and consular officials in Nigeria are in contact with local authorities to gather additional information, spokesman John Babcock said.

Canada cannot release further details on the case due to privacy concerns, Babcock said.

In October, kidnappers took four Britons in Delta state in the south. Three were released after negotiations, but the other, Ian Squire, was killed.

The Abuja-Kaduna road has long been a haunt for kidnappers. Last February, two German archaeologists were abducted in the region, though were later freed.