What you need to know:
- Schools that teach a so-called secular curriculum have been repeatedly targeted during the insurgency, which since 2009 has left at least 20,000 people dead.
- According to the UN children's agency Unicef, more than 2,296 teachers have been killed and some 1,400 schools destroyed in the wider northeast region.
Boarding schools have been closed indefinitely in the northeast Nigerian state most affected by Boko Haram violence, the government has said, in the latest blow to children's education.
"All boarding secondary schools in the state, with the exception of those in (the state capital) Maiduguri and (the town of) Biu, will close down with immediate effect until further notice," the Borno state government said.
Borno is the spiritual home of Boko Haram Islamists, whose name translates loosely from Hausa as "Western education is forbidden".
The high-profile abductions of more than 200 schoolgirls in Chibok, Borno state, in April 2014, and 110 others from Dapchi, Yobe state, in February this year also led to closures.
Schools that teach a so-called secular curriculum have been repeatedly targeted during the insurgency, which since 2009 has left at least 20,000 people dead.
According to the UN children's agency Unicef, more than 2,296 teachers have been killed and some 1,400 schools destroyed in the wider northeast region.
Muhammad Bulama, the Borno commissioner for home affairs, information and culture, said on Wednesday the decision was taken last week after a Boko Haram attack in Rann on March 1.
Three aid workers and eight security personnel were killed in the attack on the remote town near the border with Cameroon, which led to the withdrawal of aid agencies.
Schools have previously been shut in the wake of deadly attacks in Buni Yadi, Yobe state, when more than 40 students at a boys' boarding school were killed in a Boko Haram attack.
Bulama said "urgent and immediate measures" were being taken to improve security but the closures are the latest disruption to schooling in an area already hit by low levels of education.
At the start of the new academic year in September last year, Unicef said at least 57 percent of schools in Borno remained closed.
It warned the situation threatened to create "a lost generation of children, threatening their and the country's future".