Thirteen bodies were pulled from the wreckage of a building under construction that collapsed "like a house of cards" in a coastal village in the Indian tourist state of Goa on Saturday, authorities said.
The residential building caved in around mid-afternoon, when some 50 daily wage labourers, were working on the site, police said.
"We have got 13 bodies from the wreckage. We expect the death toll to rise," Goa Chief Minister Manohar Parrikar told AFP.
A witness said the building collapsed like "a pack of cards."
Fire and emergency service crews rushed to the spot. Rescue workers using cranes and bulldozers, shovels and bare hands, struggled to shift concrete slabs and other debris to free the trapped labourers.
Hundreds of onlookers stood watching the rescue efforts as police sought to shoo them away from the site, saying they were hampering access for machinery.
"The current priority is to rescue people trapped under the rubble and the government has also taken help of the army to clear the debris," Parikkar told the Press Trust of India separately.
Parrikar had been near the village to attend a state-sponsored folklore festival that was later cancelled by the government.
The building collapse, the latest in a string of deadly construction cave-ins in India recently, occurred in the seaside village of Canacona, south of the capital city of Panaji.
Initial reports said that the structure was five-storey apartment residence.
"We will immediately arrest the builder, the contractor and municipal officials involved in sanctioning this construction site," the chief minister said.
"I am personally monitoring the situation," he added.
He said that police had already filed complaints against those people involved in the construction of the building.
The bodies were shifted to a morgue at a nearby hospital.
Last September, a rundown five-storey residential block in India's financial hub Mumbai collapsed, killing 60 people.
The building had been listed by municipal authorities as needing "urgent repairs," according to local media reports.
Last April, another building collapse in Mumbai killed 74 people.
The incidents have highlighted shoddy construction and violations of the building code, amid burgeoning demand for housing in many parts of India and endemic corruption.
Falling buildings are a nationwide problem in India.
The British daily, The Guardian, collected statistics showing that 2,651 people were killed across India in 2012 due to the collapse of 2,737 structures, including houses and bridges.
Real estate experts say that many buildings collapse because construction codes are not followed and there is no attention to building safety.
In another of the worst recent Indian cases, 69 people were killed and more than 80 injured in a building collapse in the capital New Delhi in 2010.