On Thursday (26.02.15) at least 21 people were killed in two separate explosions in the town of Jos in central Plateau State and some 23 people lost their lives when a suicide bomber triggered an explosive device in Biu in Borno State. Two days earlier, 36 people were killed by explosions in two other northeastern Nigerian towns, Kano in Kano State and Potiskum in Yobe.

The frequent attacks on public buildings and open spaces - markets, schools, places of worship - highlight the vulnerability of the local population as the militant Islamist group Boko Haram wages its unrelenting insurgency against Nigeria and - more recently - its neighbors.

Frustrated by the inability of their security forces to protect them, Nigerians have been forming vigilante groups to shield themselves from the killing sprees of Islamist extremists.

One group that spoke to DW said they maintained checkpoints, searched pedestrians, vehicles and residences and provided intelligence to the Nigerian authorities.

The vigilantes are mostly teenage boys and young men in their 20s, but there are also women volunteers who search female passengers.

Fraught with danger

It is very dangerous work said Nigerian political analyst Mark Mijinyawa.

"They are exposing themselves to even greater risks than the people they think they are protecting, because the suicide bombers are coming there ready to kill themselves."

Traditional hunters are among those who have joined the fight against Boko Haram

Mijinyawa said most of the vigilantes have had no training - formal or informal - on how to protect themselves while carrying out their hazardous occupation. But they have a strong sense of idealism.

One of the volunteers doing checkpoint duty told DW it was a sacrifice but "most of the mosques and market places are manned by our people so as to bring peace and assure people that their lives and property will be protected."

Asked why he was risking his life for others, he referred to religious teaching and said "we give our time and wealth so as to make other people live in peace and harmony,"

Many have lost their lives while checking or patrolling their area.

A small number of vigilantes have received training. Mijinyawa believes the security forces should train more of them in the basics of self-defense and how to protect their territory. "I think that would go a long way to help checkmate a high level of suicide bombing," he said.

But even alert security guards and vigilantes can find it difficult to stop the determined suicide bomber. A girl thought to be as young as seven killed herself and seven others in a market in Potiskum last Sunday (22.02.2015).

Before the attack the guards and vigilantes said they had tried to prevent the girl from entering the market.

"We sent her back four times, because given her age, she did not have anything to do in the market," a vigilante leader told the AFP news agency.

"When we were screening people, she bent and tried to pass under the ropes, some distance from our view. That was when the explosives went off," he said.