Their (ISIS) attacks have left at least 2,600 people dead, half of them civilians, and uprooted nearly 700,000 people.

Last year the jihadists grew bolder, escalating attacks and posting brazen videos of unmasked fighters waving black flags and pledging allegiance to ISIS.

In August last year they seized the town of Mocimboa da Praia again and are still in control.

- Palma attack-

Their tactics have involved burning villages and beheading locals as Mozambican troops struggle to regain ground in the remote, forested province, despite help from private military companies.

Today the militants are in control of Palma, a town just 10 kilometres (six miles) from the nerve centre of the mega gas project that represents one of the biggest investments in Africa, led by the French energy group Total.

Armed militants moved in on Palma, a coastal town of 75,000 people, from three different direction on the afternoon of March 24. Locals and some 200 workers fled.

In recent years some unemployed youths have studied abroad on scholarships from Muslim organizations and locals say many returned preaching a more radical form of Islam. In 2017, violence erupted against government targets by a few small bands, often using machetes to kill police and officials.

The rebels have grown to several hundred, they use motorcycles and are now well-armed with automatic weapons and mortars. Military experts say many weapons come from abroad.

WHAT ARE THEY CALLED?

They are known locally as al-Shabab — Arabic for “youth” — but it seems to be just a handy nickname as they don't have any known affiliation with Somalia's jihadi rebels of the same name.

For a few years, the insurgents didn't appear to be linked to any group, but in 2019, the Islamic State group began claiming responsibility for their attacks, calling them the Islamic State Central African Province.