The United States has vowed to support Mozambique after a prolonged deadly assault on the key northern town of Palma by Islamic State-linked militants waging an escalating insurgency.

Dozens of people were said to have been killed in a raid by Islamist militants in Mozambique, as an upsurge of violence threatens billions of dollars worth of energy projects in one of Africa’s poorest nations.

Islamic State said on Monday its fighters had carried out an attack on the Mozambique town of Palma, where dozens were killed, thousands displaced and some remain missing.

The key northern Mozambique town of Palma was all but deserted on Monday, its residents fleeing by road, boat or on foot as the Islamic State group claimed control after a prolonged onslaught.

Coronavirus restrictions have exacerbated hunger in urban Zimbabwe, where at least 2.4 million people are now struggling to meet basic food needs, the United Nations said Monday.

Islamic State on Monday formally claimed an attack on the northern Mozambique gas town of Palma, the SITE intelligence group said on Monday.

Thousands of survivors of coordinated jihadist attacks in northern Mozambique's Palma town were arriving on boats in the provincial capital Pemba on Monday, according to sources in the city.

The novel coronavirus has killed at least 2 784 276 people since the outbreak emerged in China in December 2019, according to a tally from official sources compiled by AFP.

International aid agency sources say between 6 000 and 10 000 people are waiting to be evacuated to safety.

Sarah Obama, the grandmother of former US president Barack Obama, has died aged 99 in western Kenya, her daughter has told AFP.

Nothing had prepared South African mother Meryl Knox or her family for the "numbing" news following a deadly attack in neighbouring Mozambique.

More than 1 000 people were ferried to safety via boats.

Militants who seized the northern Mozambique town of Palma this week, murdering residents and forcing energy giant Total to suspend work on a nearby gas project, have wreaked havoc in the area for more than three years.

Dozens of people were still unaccounted for Sunday following a deadly Islamist attack on Mozambique's northern town of Palma, while thousands of survivors were being evacuated to the provincial capital Pemba, various sources said.

The epic Suez Canal blockage was initially blamed on strong winds and dust storms. Now, authorities say "human or technical error" could be vital factors.

Islamist militants have seized control of a town in northern Mozambique, killing several people including at least one foreign worker, and forcing France's Total to suspend operations at a huge gas project.

Residents, expatriates and other contract workers have come under attack in a three-day siege of Palma, situated in Cabo Delgado province in Mozambique.

At least 32 people were killed and 66 injured Friday when two passenger trains collided in southern Egypt, the health ministry said, the latest deadly rail accident to hit the country.

Kenya's President Uhuru Kenyatta restricted travel in the capital Nairobi and four other counties.

Eritrea will pull its troops out of Ethiopia's northern Tigray region, Ethiopian Prime Minister Abiy Ahmed has said.