DAKAR, Senegal (AP) — Two teenage girls carried out suicide bombings in a northern Cameroon village on Sunday, killing at least 9 and wounding 29 others, the country's government spokesman said, blaming Nigeria's Islamic extremist group, Boko Haram.

The Cameroon bombings come after five coordinated suicide bombings in neighboring Chad on Saturday, which killed at least 36 people and wounded some 50 others in a village near Lake Chad that is home to thousands of Nigerians who fled the militants' violence in their country.

In Cameroon, the early morning attack on Sunday hit a food market in Kangeleri near Mora town in the country's north, said Cameroon's Minister of Communications Issa Tchiroma Bakary.

Boko Haram has used dozens of girls and women in recent suicide bombings in Nigeria, Chad, Cameroon and Niger, raising fears it is using kidnap victims to target countries that have pledged to contribute to a regional force to combat the insurgents.

"They have shifted their tactics. They have noticed it is impossible to face our forces, so they are now using young girls or young boys with explosives, who go more undetected, in areas they are told to go," said Cameroon spokesman Bakary. He added it is difficult to know if the young girls know that they will die. "We guess that they use the girls who were kidnapped here and there, they brainwash them and use them."

He said the extremists are trying to spread terror, after pledging allegiance to the Islamic State group earlier this year.

Amnesty International says the Nigeria-born Islamic extremist group has killed about 20,000 people in its six-year uprising.