A four-storey under construction building collapsed in Ullawas of Gurugram in the wee hours on Thursday. As many as seven people are trapped in the rubble of the building. According to a PTI report, the Gurgaon Fire Department control room received a call at 5.15 am from a local about the building collapse in Ullawas village. Rescue teams along with the district administration, local police, fire department and national disaster management team are at the spot. Meanwhile, three NDRF teams have rushed to the site of building collapse in Ullawas. "Rescue teams are still searching for trapped labourers by removing heavy concrete material and iron grills. Efforts are on to save them," Gurgaon Police PRO Subhash Bokan said. #Haryana: Three NDRF teams rushed to the site of building collapse in Ullawas, Gurugram. More than five people are trapped after a four-storey building collapsed early morning today pic.twitter.com\/42P4vlEL7i \u2014 ANI (@ANI) January 24, 2019 Sanjeev Singla, SDM Gurugram said that the building was unstable and was being built without any technical expertise. "Rescue teams are facing difficulty as they are removing concrete, iron grills, debris. There could be seven people, all labourers, feared trapped," Isham Singh, a fire officer, said. The incident happened when work was underway to lay the lantern for the fourth floor of the building, a PTI report said, adding that police are on the lookout for the owner of the building, a resident of Ullawas village. Vinay Pratap Singh, Gurugram Deputy Commissioner said that NDRF and SDRF teams are present at the spot. "The rescue operation is underway. The owner of the building has been traced. Cause of the building collapse can be ascertained only after investigation," Singh said.