At least 18 people died after a portion of an under-construction flyover collapsed in Uttar Pradesh’s Varanasi city on Tuesday, ANI reported. Several labourers are feared trapped under the debris. Two pillars of the flyover collapsed bringing down a concrete slab over a local bus and several cars, NDTV reported.

Officials said the toll is expected to rise. “I cannot state the cause of the incident till an investigation is conducted,” Project Manager KR Sudan told ANI.

Chief Minister Adityanath told ANI that he has asked Deputy Chief Minister Keshav Prasad Maurya and minister Neelkanth Tiwari to visit the site. Adityanath said he has set up a committee to investigate the incident. The chief minister also announced Rs 5 lakh as compensation for families of those who died in the incident and Rs 2 lakh for those injured.

The local administration has deployed at least three machines to remove the debris, Zee News reported. A boundary wall has been demolished to allow construction vehicles to assist in rescue operations. Seven National Disaster Response Force teams are at the site, Principal Secretary for the Home Department Arvind Kumar told the news agency.

Prime Minister Narendra Modi took to Twitter to express his sadness over the incident. “I spoke to Uttar Pradesh Chief Minsiter Adityanath about the situation,” Modi said. “The state government is monitoring the situation very closely and is working on the ground to assist the affected.”

The Congress condoled with the victim’s families. “Our thoughts are with the families of those who have lost their lives. We wish those who are injured a speedy recovery,” the Opposition party said on Twitter.