Gunmen ambushed and shot at police in Northern Ireland overnight and officers returned fire in a further incident of increasing violence in the province.

The ambush took place in the village of Garrison, police said on Sunday, some 25 miles (40km) from Enniskillen where a 1987 bomb killed 11 people, one of the deadliest attacks during Northern Ireland's 30 years of sectarian strife.

No police were hurt in the attack.

A local member of Northern Ireland's regional assembly pointed to Republican splinter groups as the likely perpetrators of the latest shooting.

"Residents ... have said they believe dissidents were behind the attack and there is revulsion within the community that people of this ilk can take their twisted ideologies onto the streets of Fermanagh," Tommy Gallagher, a member of the moderate Irish nationalist SDLP party, said in a statement.

Sporadic violence in Northern Ireland has increased in recent months since Republican dissidents killed two British soldiers and a police officer in two separate attacks in March, threatening a decade-long peace process.

The March killings marked a low point since a 1998 peace deal mostly ended 30 years of conflict between the IRA, seeking a united Ireland, and groups wanting to maintain British control of the province.

Also late on Saturday, a car was driven through the security barrier at the Belfast headquarters of the Northern Ireland Policing Board before bursting into flames, police said.

The board is a watchdog meant to ensure impartial policing in the province. No one was injured in the attack.

Just three days ago, army experts defused a bomb which they said also targeted police officers.