At least 10 people have been killed and about 20 injured in a bomb blast near an army barracks in northern Nigeria, local officials say. The explosion hit the Mamy market in the city of Bauchi late on Sunday. The injured were taken to hospital. No group has so far said it carried out the blast. It came just hours after Goodluck Jonathan was sworn in as Nigeria's president for a new four-year term in the capital Abuja. Another - smaller - explosion hit a beer parlour on the outskirts of Abuja, causing minor injuries, officials say. The cause of the blast was not immediately known. Popular spot The blast at the popular Mamy market happened at about 2000 local time (1900 GMT), officials said, describing it as "powerful". Other reports say there were three explosions in quick succession. "There were lots of people since it's a Sunday evening. People were relaxing, eating and drinking," Bauchi state police commissioner Abdulkadir Indabawa was quoted as saying by the AFP news agency. Army barracks in Nigeria sometimes contain small market areas where traders sell food, drink and other goods to soldiers and civilians. All roads leading to the barracks were sealed off by security personnel. Earlier on Sunday, Mr Jonathan was sworn in as president during a lavish ceremony in Abuja, following his clear election victory. Mr Jonathan was promoted from vice-president after Umaru Yar'Adua died in office in 2010. The April election was largely considered free and fair, but hundreds of people were killed in three days of rioting following the announcement of the result. Mr Jonathan, 53, won nearly 60% of the vote. He is a southern Christian and had defeated his leading challenger from the mainly Muslim north. Analysts say that Mr Jonathan will have to tackle the continuing Christian-Muslim conflict and also the simmering tension in the oil-producing Niger Delta. Source: BBC