YAOUNDE, Cameroon (AP) — Cameroon's President Paul Biya has been inaugurated for his seventh term in office, amid rising separatist troubles.

As the 85-year-old leader, who has been in power since 1982, was sworn into office Tuesday his political opponent Maurice Kamto and four of his supporters were detained after a protest gathering declared Kamto victor of the Oct. 7 elections.

Violence has increased in the North West and South West regions where armed separatists are fighting for an independent state.

On Sunday, 79 pupils and three staff members were abducted from a school in the northwest. Cameroon also faces threats from Boko Haram extremists crossing the border from Nigeria.

Biya on Tuesday asked all fighters to drop their guns, threatening military action. He said he would work to return peace to Cameroon.