Nigerian security sources confirm that the attack by suspected militants on the security convoy killed policemen, soldiers, government-backed militia members and civilians.

Emergency personnel collect bodies following an attack by suicide bombers at the outskirts of Maiduguri, Nigeria, February 17, 2017. (File photo)
Emergency personnel collect bodies following an attack by suicide bombers at the outskirts of Maiduguri, Nigeria, February 17, 2017. (File photo) (AP)

The death toll from a militant attack on the convoy of the regional governor in northeast Nigeria has risen to 30.

Two sources told AFP fatalities from the attack in restive Borno state had doubled as more bodies were found and now included 12 policemen, five soldiers, four members of a government-backed militia and nine civilians.

"The tally has increased to 30 as many bodies were picked in the surrounding areas after the attack," one of the sources said, adding that "many people were injured".

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Sources had earlier told AFP that a convoy transporting Borno governor Babagana Umara Zulum came under attack from insurgents on Friday near the town of Baga on the shores of Lake Chad.

A second security source gave the same death toll of 30 from the assault and said the militants seized eight vehicles.

"The terrorists made away with an armoured personnel carrier, a gun truck and six sports utility vehicles in the convoy," the source said.

Police confirmed in a statement that the attack by suspected militants on the "security convoy" had killed eight policemen and three government-backed militia members.

It said 13 other people had been wounded and the attack had been "successfully repelled".

Zulum -- who sources said was unhurt in the attack -- had flown to the area to prepare for the return of residents displaced from Baga by the conflict.

He was driving in the convoy accompanied by government officials under tight security towards Baga ahead of the arrival of the returnees.

READ MORE: Suspected militants attack Nigeria's Maiduguri city

ISWAP attacks

The Daesh-affiliated Islamic State West Africa Province (ISWAP) group maintains most of its camps on islands in Lake Chad and the region is known as a bastion for the militants.

The militant group has recently intensified attacks on military and civilian targets in the region.

In July Zulum's convoy came under gun attack from ISWAP outside Baga, forcing him to cancel his trip to the town.

36,000 people killed

The decade-long insurgency in northeast Nigeria has killed 36,000 people and forced over 2 million from their homes.

Most of the displaced have been housed into squalid camps where they depend on food handouts from international charities.

Local authorities have been encouraging the displaced to go back to their homes despite concern from aid agencies of the security risks.

ISWAP splintered from the main Boko Haram group in 2016 and has gone on to be the dominant insurgent force in the region.

Source: AFP