MAIDUGURI - At least 65 people were killed during an attack by militant group Boko Haram near Nigeria's northeastern city of Maiduguri, a Reuters reporter said after counting bodies at a hospital morgue.

The remains of a dozen victims were burnt beyond recognition in Saturday's attack when militants opened fire on residents, set fire to houses and targeted a crowd with suicide bombers, security and medical officials said.

A Nigerian military spokesman, Colonel Mustapha Ankas, said that Boko Haram militants attacked the community of Dalori, about 5 km (3 miles) east of Maiduguri in Borno state.

It was the third attack this week suspected to have been carried out by the insurgent group - and the most deadly. Since it started losing control of territory, Boko Haram has reverted to hit-and-run attacks on villages as well as suicide bombings on places of worship or markets.

In neighbouring Adamawa state, a suicide bomber believed to be a Boko Haram militant killed about 10 people on Friday and at least 12 were killed on Wednesday in an attack on the Borno state village of Chibok, from where over 200 schoolgirls were abducted in 2014.

Ankas said insurgents entered Dalori in two cars and on motorcycles and opened fire on residents and burned down houses. "While people were running for their dear lives...three female suicide bombers attempted to make their way into the crowd...and subsequently got blown up," he said without providing a casualty figure.

An official of the state emergency agency who was at the scene said there were 12 bodies burnt beyond recognition. "We can't even pick those ones, they were seriously burnt," the official who declined to be named said.

Borno state capital Maiduguri was struck by several bombs at the end of December that killed at least 48 people.

The state is the heartland of the seven-year insurgency that seeks to establish an Islamist state. Over 2 million people have been displaced and thousands killed. Maiduguri has swelled to double its size over the last few years to around 4 million as it has become the refuge for most of the displaced population.

Separately, twin suicide attacks by suspected Boko Haram militants killed at least three people in two locations near Lake Chad, around 100 km (60 miles) north of the Chadian capital N'Djamena, security sources said. At least one other would-be bomber was reported to have taken flight, they added.

Meanwhile, suspected militants in southern Nigeria have blown up oil pipelines operated by a subsidiary of Italy's Eni, causing a "massive" oil spill, an industry official said Sunday.

"The attack on the Agip pipelines in Brass was carried out by suspected Niger Delta militants on Thursday night," an official from the state-run oil company NNPC, who did not want to be named, told AFP.

He said explosives were used to blow up the pipelines in the oil-rich state of Bayelsa. "The explosion has led to a massive spillage of crude into the sea and fishing camps while residents of the communities now live in fear," he said.

Brass is home to a crude oil exports terminal. The official could not say if oil exports were affected.

No group has claimed responsibility for the attack, which comes a few weeks after several pipelines and oil facilities were blown up in nearby Delta state, home of former militant leader Government Ekpemupolo.

A federal high court in Lagos this month ordered Ekpemupolo's arrest over allegations he defrauded the state of more than $175 million (161 million euros) between 2012 and last year in tainted government contracts.