The United States condemns the "vicious" attacks by insurgents in Nigeria that had killed dozens of civilians, the State Department said on Tuesday.

Insurgents of the radical Boko Haram group attacked a community in the Nigerian northeast state of Borno on Sunday, killing 85 people and leaving 50 others injured. On the same day, gunmen attacked a village church in the state of Adamawa, shooting dead nine people and injuring 15 others.

"We support Nigerian authorities as they begin to investigate these attacks, and urge citizens to support their efforts to bring the perpetrators to justice," State Department spokeswoman Jen Psaki said in a statement.

The US remains committed to helping Nigerian government as it works to counter the threat posed by Boko Haram and associated groups, Psaki said.

Founded in 2001, Boko Haram, a nickname meaning "Western education is forbidden," is a US-designated terrorist organization.

The US held the group and its splinter group Ansaru responsible for thousands of deaths in northeast and central Nigeria in the past few years, including dozens of attacks on churches and mosques, targeted killings of civilians, and the 2011 suicide bombing of the UN building in Abuja that killed 21 people and injured dozens more.