Boko Haram fighters battled Nigerian soldiers for about an hour on Wednesday as they tried to take over a military base, in the latest attack against troops in the restive northeast.
A former local government official, a civilian militia member and a motorist who witnessed the shooting said the Islamist militants tried to storm the outpost in the village of Mainok in Borno state.
Troops managed to repel the attack with the help of reinforcements but it comes after a series of similar raids targeting soldiers that is likely to stoke fears of a resurgence.
Lawan Bukar Wasaram, a former chairman of the Kaga district where Mainok is located, said "large numbers" of Boko Haram militants tried to take over the base.
"So far, 14 of the attackers have been killed and two of their (pick-up) trucks impounded," he told AFP. "The situation has been brought under control by troops."
A leader of the civilian militia in the Borno state capital, Maiduguri, some 60 kilometres east of Mainok, gave a similar account, although he put the death toll at nine.
"They attempted to overrun the military base but troops fought back. They had reinforcements," he added.
Motorist Laminu Isa was travelling to Maiduguri from the capital of neighbouring Yobe state, Damaturu, when he and hundreds of other drivers were caught up in the shooting.
"We had to turn to nearby Jakana village and waited until the fighting stopped," he said.
"They came in eight pick-up trucks. We saw them when they crossed the roads and many of us stopped in panic. But they told us they weren't after civilians.
"Their main target was the military so they touched no-one among the motorists."
Isa said the gunmen came from the direction of Buni Yadi in Yobe, which links up with the Sambisa Forest in Borno — the long-time base of factional leader Abubakar Shekau.
An increase in attacks, including against "hard" military targets, was expected as it has happened before when the Nigerian Army changed senior commanders in the northeast.
Last week, Major General Ibrahim Attahiru was redeployed after just seven months in charge.
The army maintained it was a routine transfer but it followed increased violence in recent weeks, including a suicide bombings that caused heavy civilian casualties.
At least six soldiers died in two separate Boko Haram ambushes earlier this month near Damboa, south of Maiduguri.
The upsurge in attacks could also be an indication that Boko Haram is feeling pressure and is fighting back to secure weapons, ammunition, food and supplies.
The Maiduguri-Damaturu-Kano road was once one of the most dangerous routes for motorists in the northeast, where at least 20,000 people have been killed in the insurgency since 2009.
In September 2013, at least 167 people were killed when Boko Haram gunmen barricaded the highway in Benisheikh, near Mainok.
Jakana and Mainok were also attacked and burnt in March 2013, killing about 80.
In September 2014, jihadists fired a rocket-propelled grenade and sprayed Mainok market with bullets.