Twenty-two people have died following a landslide at an illegal mine in northern Tanzania, officials said.

The incident occurred at Ng'alita mine in Bariadi district, Simiyu region on Saturday, district commissioner Simon Simalenga said.

It occurred after a group of people started mining in an area where activity was restricted due to heavy rains, he told Reuters news agency.

President Samia Suluhu Hassan expressed her "great sadness" at the news.

"These fellow Tanzanians were small miners in the area, trying to earn a living for themselves, their families," she said in a post on X, formerly known as Twitter.

Mr Simalenga said he was initially told that there were 19 to 20 people trapped in the mines, but that 22 bodies ended up being retrieved.

Faustine Mtitu, acting commander for the region's fire and rescue forces, said in quotes cited by AFP news agency that the search had been ended as he was "convinced that there are no more bodies trapped in the rubble."

Mr Simalenga said the group of people began mining in the mineral-rich area about three weeks ago before the government brought in safety procedures.

The area was restricted because of ongoing heavy rains, which have caused flash floods.

"The regional mining officer visited them and stopped them from mining as it was working on the required procedures" Mr Simalenga said.

Unregulated and illegal mining is common in Tanzania, which is one of the largest gold producers in the world.