Douala: Five pupils are missing after gunmen attacked a high school in an English-speaking part of Cameroon, severely injuring the principal, sources said Tuesday.

The attackers targeted a school in Bafut, a town near Bamenda - the capital of the secessionist North-West region - on Monday, the first day of the new academic year, a witness told AFP.

A source close to the school's administration confirmed the report.

Seven pupils and the school principal were initially reported missing after the attack.

Two youngsters and the headmaster were later released, though the principal was seriously injured, the school source said.

Separatist unrest in Cameroon's two minority English-speaking regions - North-West and South-West - has left scores dead and displaced about 200,000 people since late 2016.

Years of resentment at perceived discrimination at the hands of Cameroon's majority French speakers have led to almost daily acts of violence and retribution, triggering an army crackdown.

A total of 109 members of the police and security forces have been killed, according to government figures.

The separatists, who say the education system marginalises anglophone pupils, have decreed a boycott of schools in the areas they lay claim to.

Some secessionists said on social media that they could not guarantee the security of children who returned to school in defiance of the boycott.

A witness told AFP that school turnout was low in Bamenda on Monday.

School principals are frequently targeted by armed men identified as secessionists.

At the start of the 2017 school year, several schools were burnt in the anglophone zone.

English speakers count for about a fifth of the West African country's population of 22 million people.

The conflict poses problems for the organisation of presidential elections set for October 7, in which incumbent Paul Biya will seek a seventh consecutive term.