Activist groups estimate as many as 16 to 20 people have died of hunger or thirst on a boat that is carrying ethnic Rohingya and stranded off India's coast.
The boat, which is carrying at least 100 people and is currently in Malaysian waters, has been stranded at sea for two weeks.
"We estimate that probably as many as 20 have died … some from hunger and thirst, and others jumped overboard in desperation," said Chris Lewa, director of the Arakan Project, which works to support Myanmar's Rohingya community.
"This is absolutely awful and outrageous."
It is not clear if the boat drifted or was towed to Malaysian waters, or if India attempted to provide aid.
India's navy and coast guard did not immediately respond to requests for comment.
Each year many Rohingya risk their lives boarding rickety vessels to reach Malaysia.
"These people have been adrift on a damaged boat for more than two weeks without food and water," said Lilianne Fan, chair of Asia Pacific Refugee Rights Network's Rohingya Working Group.
"We have heard that up to 16 people may have already died."
The Sri Lankan navy rescued more than 100 Rohingya on another boat over the weekend.
In 2018, more than 730,000 Rohingya Muslims fled to neighbouring Bangladesh following a military crackdown in Myanmar that witnesses said included mass killings and rape.
Rights groups and media have documented killings of civilians and burning of villages.
Dil Mohammed, a Rohingya refugee leader in Bangladesh camps, called for urgent action to help the people on the boat..
"These people must be urgently disembarked to safety," she said.
"It's inhuman to keep them at sea after such an ordeal."
ABC/wires
