KANO, Nigeria (AFP) – Gunmen opened fire at an open-air tavern in northeastern Nigeria, killing six people, police said on Sunday, amid an upsurge in violence in the country ahead of April elections.

The motive for the attack late Friday at the tavern outside a hotel in the city of Gombe was not immediately clear and police could not provide details on the assailants. No arrests had been made.

"Six people were killed in the attack, while two others were injured, one of them critically," police spokesman Abdullahi Kamba told AFP.

Suspected members of an Islamist sect that launched an uprising last year have carried out a series of attacks in recent months in northern Nigeria, mainly in the city of Maiduguri, including raids on churches.

Bomb blasts have also occurred in the capital Abuja and the central city of Jos, while political rallies have also been targeted by violence.

Nigeria will hold presidential, legislative and state elections in April.