BAUCHI, Nigeria - Suspected Islamic extremists struck in two state capitals in northeastern Nigeria on Monday, killing at least seven people and injuring dozens with a double bombing at a crowded market and an attack on a police base. Around 30 extremists were also killed in clashes with security forces, police said.

The attacks were the latest in a week of violence linked to Islamic militants that has killed more than 170 people in northern Nigeria.

Police spokesman Gideon Jubrin said at least five people were killed at a market in Maiduguri, the capital of Borno state where two female suicide bombers also killed 70 people a week ago.

A vigilante official said two young female suicide bombers were also responsible for Monday's blasts and that they had recovered their bodies along with those of six victims. Hospital officials said they were treating more than 40 people with serious injuries. The vigilante and hospital officials spoke on condition of anonymity.

In Damaturu, the provincial capital of Yobe state about 85 miles west of Maiduguri, extremists destroyed several buildings and killed at least two doctors when they stormed the residential quarters at the general hospital, according to the Hospitals Management Board. Three other doctors were abducted.

Police there said the attackers drove State Security Service agents from their offices but were repelled, and about 30 terrorists were killed when they tried to take over Yobe Government House, where there is a military armory.

There was no immediate claim of responsibility for the Maiduguri blasts but people blamed Boko Haram, the Islamic extremist group that has carried out many such attacks in a five-year insurgency that has killed thousands and forced hundreds of thousands from their homes.

After the explosions, young men in vigilante groups barricaded some Maiduguri roads to try to ensure safety in the city.