Up to 180 migrants are reported to have been forced from a boat on Thursday by smugglers off the coast of Yemen, the UN migration agency International Organization for Migration (IOM) said.
Five bodies have been recovered so far and around 50 are reported missing the agency said.
The latest incident came barely 24 hours after smugglers forced more than 120 Somali and Ethiopian migrants into the sea as they approached the coast of Shabwa, a Yemeni governorate along the Arabian Sea.
That resulted in the drowning of around 50 migrants. The migrants had been hoping to reach countries in the Gulf via war-torn Yemen.
"The survivors told our colleagues on the beach that the smuggler pushed them to the sea, when he saw some 'authority types' near the coast," said Laurent de Boeck, the IOM Yemen chief of mission.
"They also told us that the smuggler has already returned to Somalia to continue his business and pick up more migrants to bring to Yemen on the same route. This is shocking and inhumane," he added.
Shortly after the tragedy, staff from IOM found the shallow graves of 29 migrants on a beach in Shabwa during a routine patrol. The dead had been quickly buried by those who survived the smuggler's deadly actions, said IOM.
The migration agency said it working closely with the International Committee of the Red Cross to ensure appropriate care for the deceased migrants' remains.