Rescue teams searched through the remains of a collapsed building in New Delhi on Monday as the death toll from the incident rose to six, officials said.

The five-story building, which operated as a hostel for male students, collapsed Sunday in Satya Niketan, a densely populated area known for private student accommodations near a Delhi University campus.

Police, firefighters and teams from India’s disaster response agency continued search operations for a second day. Earthmoving machines removed large amounts of debris while sniffer dogs were deployed to help locate people who might still be trapped under the rubble.

Delhi Chief Minister Rekha Gupta said rescuers had pulled at least 12 people alive from the debris. About 80% of the rubble had been removed by Monday, with only debris from the basement still left to clear.

Gupta said six people had died and six others were injured in the collapse.

Residents said the building was at least 55 years old and had been undergoing renovation for several months. Although the work was reportedly incomplete, the building was reopened to tenants, most of them students, in August.

Prakash Chand, a local resident, said workers were digging in the basement when the building suddenly collapsed.

Gupta said preliminary investigations indicated that water had accumulated in the basement and that ongoing repair work on the aging structure may have contributed to the collapse.

She said the government would introduce a policy requiring regular structural inspections and safety certificates for buildings used by the public. The proposed rules would cover student accommodations, nursing homes, schools and similar facilities.

“No public activity will be permitted” in buildings that fail to meet the required safety standards, Gupta said.

Building collapses are a frequent danger in some parts of India during the June-to-September monsoon season, when heavy and prolonged rainfall can weaken older structures and increase the risk of collapse.