YAOUNDE, Sept. 6 (Xinhua) -- President Paul Biya of Cameroon has denounced an attack on school children in the Northwest, one of the country's two English-speaking regions, communication minister and government spokesman, Issa Tchiroma said on Thursday.

"President Paul Biya has expressed indignation at the terrorist act that constitutes serious violation to the right to education", Tchiroma said in a press release.

The president has instructed the government to take adequate measures to ensure the smooth conduct of the school year throughout the country, he added.

In the Northwest region, gunmen attacked the Presbyterian Girls Secondary School on Tuesday, kidnapping six students and the principal. The principal was severely injured, witnesses said.

Tchiroma said two of the students and the principal were later released, without giving more details.

Attacks on schools and learners have increased in the troubled regions since the start of the new academic year on September 3.

Fighting between armed separatist forces and Cameroon security forces is escalating in the two regions since November 2017 following a "declaration of independence" of the regions by the separatist forces.

The armed separatist forces want the Anglophone regions to secede from the majority French-speaking nation and form a new nation called "Ambazonia".