Lions have killed three children who had gone to look for missing cattle in northern Tanzania’s Ngorongoro wildlife reserve, police said in a statement on Thursday.

The children – aged between nine and 11 – went looking for the livestock just after they had returned from school, Arusha police chief Justine Masejo is quoted by the AFP news agency as saying.

"That is when the lions attacked and killed three children while injuring one," he said.

"I would like to urge the nomadic communities around the reserved areas to take precautions against fierce animals especially when they task their children to take care of the livestock. That will help to protect the children and their families."

Ngorongoro, and other wildlife reserves and national parks, are protected areas but the authorities allow Maasai people to live there and raise cattle.

There have been cases of humans and wildlife coming into conflict before, AFP reports.

Thirty-six lions had to be relocated from the Serengeti National Park, also in northern Tanzania, after they attacked humans and cattle.