The Islamist militant group is based in northeastern Nigeria but regularly carries out raids in neighbouring Cameroon, Chad and Niger, prompting the four countries plus Benin to create a 10,000-strong joint task force.
The frequency of the attacks has dropped in recent months, although more than 1,500 people have been killed in Cameroon by such attacks, International Crisis Group said in a report this month.
Attacks were happening on an almost daily basis, but have dropped to between six and eight a month, it said.
Only one of this week’s strikes, at a military camp at Darak where six soldiers were killed, resulted in the deaths of people other than the attackers themselves, the sources said.
“Between yesterday and today there were three attacks: in Darak, in Diguina and a thwarted kamikaze strike in the Kolofata (camp),” said a senior army source who asked not to be named, referring to three places in the Far North Region of Cameroon.
On Monday, a young women armed with explosives attempted to enter a military post for soldiers adjacent to a camp for thousands of people displaced by the militant group.
“We thought it was a beggar at first but then she sped up and refused to stop when we shouted at her so she was neutralised,” said an intelligence source.
In the third incident, militants set fire to houses in the village of Diguina, the sources said.
