(CNN) -- A landslide at a huge landfill killed at least 50 people and injured dozens more outside the Ethiopian capital of Addis Ababa, Communications Minister Negeri Lencho said.

Officials were still investigating how the landslide at the sprawling Koshe landfill occurred Saturday night, Lencho said.

"It's a sad story because the government has been trying to resettle the people residing in the area," Lencho said. The government had also been building a factory to convert waste products at the landfill into energy, he said.

Security personnel are still searching for people who have been reported missing in the landslide, Lencho said, and authorities are working to find housing for the families affected.

Hundreds of people live in makeshift houses on top of the garbage at Koshe -- which means "dust."

The government has transferred 290 people who were living on the landfill, but who were not injured in the accident, to a temporary shelter in a youth center in Addis Ababa.

Many people at the landfill were "frantically looking for friends and family," Hope for Korah, a Canadian NGO that assists people living in the area near the dump, said on its Facebook page. Some of the people who were trapped in the landslide tried to call authorities to get help from inside the debris, the group said. One woman and her three children managed to scramble to safety just as their home became caught up in the landslide, according to the NGO.

A similar landslide occurred in December 2015 at a waste dump in Shenzhen, China, killing 58.