Boko Haram Islamists staged three suicide attacks in Nigerias restive northeast on Friday, leaving four attackers and two civilian vigilantes dead, police said.
"Aside from the explosion near a mobile police location in Jiddari, we had two other suicide bombings along Maiduguri-Gamboru road," Borno state police commissioner Damian Chukwu told reporters in Maiduguri, epicentre of Boko Haram's seven-year insurgency.
"This is about the sixth or seventh suspected suicide attack in the last couple of days. The police and other security agents are working hard to stop the ugly trend," he said.
The first attack took place before dawn when a female suicide bomber blew herself and another bomber up near a police checkpoint at Jiddari, Borno state police spokesman Victor Isuku earlier said,
A third suspected bomber survived and was being questioned.
"At 3:50am today, mobile police personnel on guard duty opposite the federal high court in Jiddari sighted three suspected suicide bombers comprising two females and a male running towards their sandbag," Isuku said.
"They ordered them to a halt for questioning but they refused," he said. "One of the females detonated the Improvised Explosive Device (IED) strapped to her body, killing herself and one other male accomplice," he said.
Later in the morning a male suicide bomber detonated his explosives after being stopped at the entrance of a garage on the Maiduguri-Gamboru road where traders had gathered to travel under military escort.
The bomber died instantly, police said.
Another male suicide bomber detonated his explosives on the same road a few meters away a little later, killing himself and two local vigilantes, assisting the military to fight the jihadists.
Ahmed Satomi of the Borno State Emergency Management Agency (SEMA) said five villages in Monguno had been attacked by Boko Haram insurgents early in the week, leaving eight dead and dozens injured.
"Boko Haram gunmen attacked the five villages late Monday and continued until Tuesday. They killed eight people and injured dozens," he said.
He said the victims had been evacuated by soldiers who deployed to the area.
Boko Haram, which seeks to impose strict Islamic sharia law in Nigeria's mainly-Muslim north, has killed at least 20,000 people and left more than 2.6 million homeless in its six-year insurgency.
A counter-offensive backed by a regional force has seen the Nigerian military retake swathes of territory from the insurgents, but the jihadist group still poses a security threat to civilians.
On November 1, a truck carrying eight suspected Boko Haram extremists exploded near a military checkpoint in Maiduguri, killing all the occupants.