The Somali port of Bossaso has been hit by deadly twin blasts as grenades planted in a building housing mainly Ethiopian migrants exploded overnight.
Hundreds die every year in the attempt to cross to Yemen
More than 20 people were killed in the explosions and more than 100 are seeking treatment for severe wounds.
The motive for the attack is not clear, but the port is a gathering point for those seeking to cross the Gulf of Aden to find work on the Arabian peninsula.
The north-east has been relatively calm compared to the rest of Somalia.
The regional authorities in Puntland say the attack is the first and worst of is kind.
Functioning central government collapsed in 1991 with the overthrow of President Siad Barre, leaving Somalia prey to rival warlords.
Correspondents say the attack may be connected to the long-standing rivalry in the region between Somalia and Ethiopia.
Ethiopian troops are supporting a United Nations-backed government in Somalia and there are regular outbreaks of fighting with Islamic insurgents in the capital, Mogadishu.
The BBC's Mohammed Olad Hassan in Mogadishu says nobody has claimed responsibility for the attacks in the north-eastern commercial town.
He says the grenades were reportedly buried in a makeshift residence near the port where some Ethiopians were housed.
Many Ethiopians come to Bossaso to make the dangerous crossing to Yemen or work as porters or run businesses around the port, our reporter says.
Hospital workers have described the situation as horrific with many victims having lost limbs in the explosion.
Bossaso's mayor asked all doctors and nurses in the town to come and help treat the wounded.
A reporter for the BBC's Somli Service says the dead where buried on Wednesday morning.
Puntland has become a staging post for people willing to risk the voyage across the Gulf of Aden for a better life elsewhere.
Hundreds die every year in the attempt as boats founder in its shark-infested waters.