A bombing in a bar in Nigeria's northeast has killed at least 14 people and injured another 14 in the second attack targeting football fans in a fortnight.

The blast on Sunday hit the town of Mubi in Adamawa state, one of three in the northeast which has been under a state of emergency for more than a year as Nigeria's military has tried to crush Boko Haram's five-year uprising.

Al Jazeera's Ahmed Idriss said residents in Mubi town had told him dozens were killed in the attack.

"The police are confirming, so far, 14 people have died in the blast but locals are telling us at least 40 people may have died in that attack at the moment," our reporter said from Abuja.

The bomb exploded around 6.30pm (1730 GMT) in Gavan in the Mubi area of Adamawa and reportedly targeted fans who were watching a local club match.

There was no immediate claim of responsibility.

Football fans targeted again

Last week a botched suicide bombing that was meant to target an open air viewing of a football match in the central Nigerian city of Jos killed three people

Adamawa has been hit by far fewer Boko Haram attacks than other parts of the northeast, but the area was the site of a gruesome October 2012 massacre at a post-secondary technical college.

Scores of students were killed in their dorms, including many whose throats were slit.

Mubi is just a few kilometres from Nigeria's border with Cameroon and near the area where two Italian priests and a Canadian nun were seized by suspected Boko Haram gunmen in April.

The three were released earlier on Sunday and flown out on board a military aircraft from the town of Maroua, heading for the Cameroon capital.

Boko Haram has carried out scores of attacks on targets it says are a product of Western influence, including sports venues and schools teaching a secular curriculum.

The group has killed thousands during its battle against the government since 2009, but the conflict has received unprecedented global attention over the last six weeks following the group's mass kidnapping of more than 200 schoolgirls.

The girls were seized on April 14 from Chibok in Borno state, which shares a border with Adamawa.

Nigeria's response to the kidnapping has been fiercely criticised as inept and the crisis has piled intense pressure on President Goodluck Jonathan's government to do more to end the uprising.