Suspected Islamist militants have abducted more than 100 girls from a secondary school in Nigeria’s northeastern Borno state, a teacher said on Tuesday.

“Over 100 female students in our government secondary school at Chibok have been abducted,” Audu Musa, who teaches in another public school in the area, told Reuters news agency.

The incident took place on Monday night, and is believed to have been carried out by the Islamist militant group Boko Haram, which has been known to attack schools in the country’s restive northeast.

Education Commissioner for Borno State Inuwa Kubo confirmed the kidnappings at Chibok, but told Reuters that the authorities were still trying to ascertain the exact number of girls abducted as several students fled into the bush during the attack.

Borno state’s education authorities ordered all of its schools closed last month after Islamists killed dozens of students in a February attack against a boarding school in neighbouring Yobe state.

But a Borno education official, who asked not to be named, told Reuters that the girls had been back at the Chibok school writing exams.

Boko Haram, whose name means “Western education is forbidden”, has targeted schools, villages, markets, and military barracks and checkpoints this year in increasingly frequent attacks.

The group's stated mission is to establish an Islamic state in Nigeria, which is Africa’s most populous nation with some 170 million people divided almost equally between Muslims living mainly in the north and Christians in the south.

It was officially labelled a "foreign terrorist organisation" by the US State Department last November.

(FRANCE 24 with AFP, REUTERS)