"The air strike took place on the town's weekly market day, where residents from various nearby villages had gathered to shop, resulting in the death of more than 100 people and injury of hundreds, including women and children," said the Emergency Lawyers, who have been documenting human rights abuses during the 20-month war between Sudan's army and the paramilitary Rapid Support Forces.

The air strike hit the town of Kabkabiya, about 180 kilometres (112 miles) west of state capital El-Fasher, which has been under RSF siege since May.

The lawyers said they "condemn in the strongest terms the horrendous massacres committed by army air strikes" in Kabkabiya.

In a separate incident, a drone that had crashed in central Sudan's North Kordofan on November 26 exploded on Monday evening, killing six people, including children, and leaving three others seriously injured, the lawyers said.

In Nyala, the capital of South Darfur, a series of "indiscriminate airstrikes" also targeted three neighbourhoods with barrel bombs, they added.

The attacks are part of "an ongoing escalation campaign, contradicting claims that the air strikes target only military objectives as the raids are deliberately concentrated on densely populated residential areas", the lawyers said in a statement.

Both the army and the RSF have been accused of targeting civilians and deliberately bombing residential areas.

Tens of thousands have been killed in the war and over 11 million displaced, creating what the United Nations describes as the world's largest displacement crisis.