Police have registered an FIR under sections of culpable homicide not amounting to murder, negligent conduct in connection with construction or repair of buildings, and acts endangering life or personal safety. (Express Photo: Praveen Khanna)One of the students injured in the five-storey PG building collapse in South West Delhi’s Satya Niketan is a key witnesses the Delhi Police is relying on to frame charges against the property’s operators, The Indian Express has learnt.Nitish Chib (19) was a tenant at the PG, which was run from building 14 by ‘Hostel Days’, operated by Sudhanshu Lovneesh and Subham Tyagi. Both were arrested after the collapse on Sunday claimed seven lives.When the structure came crashing down on Sunday, killing seven people – including five of Chib’s fellow tenants – he was among those rescued.Chib, who is from Raipur village in Jammu’s Satwari area, was living in room 202. In his statement to the police, he said construction work in the basement had been going on for 10-12 days.He and other students had complained to Lovneesh and Tyagi about the noise and the cutting of iron rods on the ground floor, court documents showed.“Chib said both Sudhanshu and Shubham allegedly told him that the PG would be extended to the basement and allegedly threatened to expel him from the PG if he objected,” the source added.Sources further said that the police will use Chib’s statement, among other evidence like the lease papers of the property, to prove that Hostel Days was not merely a operator watching the construction from the sidelines, but was actively promoting it, and threatening anyone who warned the operators about it.Story continues below this adEarlier, police sources had said a plumber warned Lovneesh hours before the collapse that the building’s wall could give way because of the construction.While Lovneesh was arrested on Wednesday, Tyagi reached the police station and surrendered on Friday. He was produced in court and sent to two-day police custody.Though Tyagi had earlier reportedly claimed that he only contributed financially to the PG operation, police have allegedly found that the building was leased to both him and Lovneesh last year. While the upper ground and first floors were leased to Lovneesh, the second and third floors were leased to Tyagi.Besides Lovneesh and Tyagi, building owner Hariram, his wife Urmila, their son Mahesh and labour contractor Saroj were arrested earlier this week.Story continues below this adAccording to the police, the owner had permission to construct only the first and second floors of the building, but three additional floors were later added. The ongoing basement construction, which the owner allegedly said was undertaken to address seepage, further weakened the structure.Lovneesh and Tyagi were in charge of installing the 16-bed facility with amenities, looking after maintenance, and overseeing the repair and construction work needed at the decades-old building.They ran similar units in other parts of the area too. Lovneesh was the main person prospective tenants met when they came looking for rooms, police have said.