Suspected members of Islamist group Boko Haram have killed at least eight people, including a policeman, in separate attacks in restive northern Nigeria, police said Friday. The attacks, which also wounded a policeman, occurred in three different cities, with most of the violence in Maiduguri, the capital of Borno state in Nigeria\'s northeast where Boko Haram has been based. \"Five people were killed yesterday by gunmen suspected to be Boko Haram, in a bakery. All five were laborers in the bakery, located in the Polo area of Maiduguri,\" Borno state police commissioner Bala Hassan told Agence France Presse. He said two gunmen stormed the bakery with guns concealed in a sack and shot the five dead. The attackers fled before police arrived, he said. Hassan said a customs officer was shot dead on Wednesday at Gamboru market in Maiduguri, while a water vendor was also killed in another area of the city on the same day. In nearby Yobe state, police spokesman Toyin Gbadegeshin told AFP a policeman was killed outside his house in the state capital on Thursday. \"We lost a policeman to unidentified gunmen who trailed and killed him outside his house at Pawari neighborhood of Damaturu,\" he said, adding that Boko Haram was suspected. In yet another attack, a policeman was wounded by gunmen who opened fire on him outside a petrol station in Kano, the largest city in Nigeria\'s north. Boko Haram has been blamed for scores of shootings and bomb blasts, mostly in northern Nigeria, in an increasingly deadly insurgency that has killed more than 1,000 people since 2009. Criminal groups have also carried out violence and robberies under the guise of Boko Haram. The US embassy in Nigeria warned Wednesday that Boko Haram may be planning attacks against hotels or other targets in the Nigerian capital Abuja, but the government downplayed the alert and said there was no cause for alarm.