A bomb attack in the north-eastern Nigerian town of Maiduguri has killed at least 25 people and wounded dozens, security sources say.
They say they believe the attack, which occurred in a beer garden, was carried out by the Islamist sect Boko Haram.
The group wants to establish an Islamic government in Nigeria.
It has carried out a number of bombings in north-eastern Nigeria, as well as an attack on police headquarters in the capital Abuja earlier this month.
Gunmen on two motorcycles attacked a packed beer garden late on Sunday, officials said.
"The attackers believed to be Boko Haram members threw bombs and fired indiscriminate gun shots on a packed tavern at Dala Kabompi neighbourhood, killing at least 25 people and seriously injuring around 30 others," an unnamed police officer told the AFP news agency.
Eyewitness Emmanuel Okon told AFP: "I just heard a loud bang followed by sporadic shootings and plumes of black smoke filled the area with people screaming and running in all directions."
The police have not officially said how many people died in the attack but correspondents say that if 25 people have been killed, it would be the most deadly attack yet carried out by Boko Haram.
The BBC's Bilkisu Babangida in Maiduguri says there is a mood of fear in the city, with many people staying indoors as they are afraid of being caught up in an attack.
Gunmen believed to be from Boko Haram also staged two attacks in the town of Gamboru-Ngala, in Borno state near the border with Chad, on Sunday:
At least one person was killed after shots were fired at the funeral of a local politician, who had been killed by suspected Boko Haram fighters on Saturday, witnesses told the BBC
An Islamic scholar was also shot dead
The group has killed dozens of people, mainly security officers and politicians, in Borno state over the past year.
Earlier this month, the group said it was behind the bombing of the national police headquarters in the capital, Abuja.
It has also said it carried out attacks on the inauguration of President Goodluck Jonathan in May.
The group's trademark has been the use of gunmen on motorbikes.
A Christian preacher, a Catholic church, Muslim clerics who have criticised Boko Haram, and last week, a nurse playing cards, have also been targeted.
Its leader Mohammed Yusuf and several hundred of his supporters were killed by security forces in Maiduguri in 2009 after the group attacked police stations.
