The photo taken on July 26, 2015 shows the explosion site in Maroua, capital of Far-North Region in Cameroon. The death toll of a suicide bomb attack which took place on Saturday in Maroua rose to 21, one army source told Xinhua on Sunday. (Xinhua)

YAOUNDE, Aug. 21 (Xinhua) -- At least four people were killed and several others injured in a suicide bomb attack Sunday morning in Mora, a town of the Far North Region of Cameroon near the border with Nigeria, security sources told Xinhua by phone.

The attack was committed by an unidentified man who ran into a group of people at the entrance of a local market and detonated the bomb fastened on his belt, the sources said.

The sources said, "on site at least four people including the bomber himself were killed and several others injured."

Sunday is a regular market day in Mora, a base of the multinational joint force created in 2015 by Lake Chad Basin Commission to fight against Boko Haram.

Cameroonian security forces suspected Nigerian Islamic sect Boko Haram was behind it. The Boko Haram has made Cameroon, Nigeria, Chad and Niger their targets with the purpose to create a caliphate.

Since July 2015, more than 100 people were killed in the Far North Region in such attacks.

Cameroon strengthened its surveillance in the Far North Region in order to stop this terrorist threat.