MAPUTO — Suspected jihadists on Monday attacked military barracks and ringed a northern Mozambican town, hoisting their flag before retreating, local security sources said.

The attack took place in Mocimboa da Praia, where a shadowy jihadist group first launched its offensive in October 2017.

Locals call the group Al-Shabaab, but it is not linked to the group of the same name operating in battle-scarred Somalia.

"Evildoers burst into the main town of Mocimboa da Praia and began exchanging shots with the defence and security forces," national police commander Bernardino Rafael told reporters in the capital Maputo.

Police spokesman Orlando Mudumane said the attack was launched before sunrise and that the insurgents had "hoisted their flag" in the town, situated a few kilometres from a major gas exploration site.

Another police officer in Mocimboa da Praia said that "the attackers surrounded virtually the entire small town and now control the air base, the port and the police stations".

"They placed barricades on the road to prevent reinforcements from arriving," the officer said.

By end of the day the attackers left the town, but not after destroying and ransacking government and military institutions.

"Around 6pm (1600GMT) the militants decided to retreat," said a military source, adding that an initial assessment showed that the local government head office, the mayor's office, commercial banks and the military barracks were destroyed.

"They took weapons,... motorcycles, destroyed the port, burnt... buses (and) have taken some vehicles from the municipality which they used to transport goods," said the source.

The faceless group has killed more than 700 people, according to the medical charity Doctors Without Borders (MSF), causing hundreds of thousands to flee the gas-rich region and raising concern among energy giants.

The insurgents have so far mainly targeted remote villages in Cabo Delgado, Mozambique's northernmost province.

Mocimboa da Praia has not been targeted since October 5, 2017, when the group's members stormed a police station and a military post.

French company Total owns a US$25 million stake in a liquified natural gas project around 60 kilometres from Mocimboa da Praia.

President Filipe Nyusi vowed to stem the Cabo Delgado attacks after he was sworn in for a second five-year term in January.

But government troops have been struggling to restore order, despite pressure by oil giants to deploy more soldiers in the area. — AFP