Crowds gathered at the site of the tragedy in an isolated and mountainous area of South Ethiopia regional state as some people clawed through mounds of red dirt, according to images posted on social media by the local authority.
So far, 148 men and 81 women are confirmed to have lost their lives after the disaster struck on Monday in the Kencho-Shacha locality in the Gofa Zone, the local Communications Affairs Department said in a statement.
Five people had been pulled alive from the mud and were receiving treatment at medical facilities, the government-owned Ethiopian Broadcasting Corporation reported earlier.
It quoted local administrator Dagemawi Ayele as saying that most of the victims were buried after they went to help local residents hit by a first landslide following heavy rains.
Dagemawi said that among the victims were the locality's administrator as well as teachers, health professionals and agricultural professionals.
Images posted by the Gofa authority showed residents carrying bodies of the dead on makeshift stretchers, some wrapped in plastic sheeting.
"Initially, four households were affected by the landslide, and later households in the area were mobilised to save lives," Firaol Bekele, early warning director at the Ethiopian Disaster Risk Management Commission (EDRMC), told AFP.
"But they too perished when the landslide engulfed them," he said, adding that the commission had sent an emergency team to the area, along with food and other aid for the stricken community.
Ethiopia, the second most populous country in Africa with around 120 million people, is highly vulnerable to climate disasters including flooding and drought.
"I am deeply saddened by this terrible loss," Ethiopian Prime Minister Abiy Ahmed said on X.
"Following the accident, the Federal Disaster Prevention Task Force has been deployed to the area and is working to reduce the impact of the disaster."
'Hearts and prayers'
African Union Commission chief Moussa Faki Mahamat also posted a statement on X, saying "our hearts and prayers" were with the families of the victims.
World Health Organization chief Tedros Adhanom Ghebreyesus, who is Ethiopian, sent a message of condolence on X and said a WHO team was being deployed to support immediate health needs.
The area is hard to access, located roughly 450 kilometres (270 miles) from the capital Addis Ababa or about a 10-hour drive.
"This isn't the first time this type of disaster has happened," said an Ethiopian refugee living in Kenya who is from a district located near the site.
"Last year in a similar disaster more than 20 people were killed and before that almost every rainy season people die because of landslides and heavy rains in that area."
Disaster management official Firaol Bekele said there needed to be a "solid assessment and scientific investigation" into the cause of the landslide.
"An integrated, study-based solution is needed to address the risk permanently. This may include relocating the population."
South Ethiopia state had already been battered by the seasonal rains between April and early May, causing flooding and mass displacement, according to the UN's humanitarian response agency OCHA.
It said in May that floods affected more than 19,000 people in several zones, displacing over 1,000 and causing damage to livelihoods and infrastructure.
In 2016, 41 people were killed in a landslide following heavy rains in Wolaita, also in South Ethiopia.
In 2017 at least 113 people died when a mountain of garbage collapsed in a dump in the outskirts of Addis Ababa.
The deadliest landslide in Africa was in Sierra Leone's capital in Freetown in August 2017 when 1,141 people perished.
Mudslides in the Mount Elgon region of eastern Uganda killed more than 350 people in February 2010.