At least 26 people died from hunger in the semi-autonomous Jubbaland region of southern Somalia in just a day an a half, federal government radio said on its website.
Somalia, like other countries in the region, is facing a devastating drought that has killed livestock, cut harvests and left 6.2 million people, about half its population, in need of food aid.
The acute hunger gripping Jubbaland caused an exodus of hundreds of families into the capital Mogadishu seeking help.
The website quoted Mohamed Hussein, the Jubbaland assistant minister of interior, as saying severe drought had killed the people over a span of 36 hours to Monday, all in various towns in middle Jubba and Gedo areas.
"The people in those areas need emergency assistance," Hussein said in the report.
Residents said most of the affected towns were controlled by al Shabaab militants, who have been waging a violent campaign to topple the Western-backed federal government in Mogadishu.
Among a group of nine families arriving in the capital from Jubbaland on Tuesday was Ibrahim Abdow, 62, who said he rode on a donkey and a bus to get there.
"Our cows and farms have perished. The rivers have dried and there are no wells there," he told Reuters, while camping under a tree on the outskirts of Mogadishu.
Residents of the city supplied the families with bread and bowls of water but they said relief food from aid agencies was needed urgently.
Rich countries must do more to stop Somalia from sinking into famine, the head of the United Nations said this month, warning terrorism would increase without aid. It is asking for US$825 million in aid.