Police have arrested a labor contractor following a major breakthrough in the investigation into the collapse of a five-story paying guest (PG) accommodation in the Satya Niketan area.

Investigators revealed Thursday that a load-bearing main wall on the ground floor was removed on the day of the collapse to make room for a new shop. The structural alteration compromised the building's integrity, causing it to collapse like a house of cards. The disaster left seven people dead, including five students, and injured five others.

Police officials said water had accumulated in the basement following recent rains, prompting renovation work over the past 8 to 10 days. Three truckloads of debris were dumped in the basement to bring it to ground level.

The labor contractor, Sanoj Kumar, was arrested in Kasganj, Uttar Pradesh. Kumar told police he was hired for the job by Mahesh, the son of the building's owner, at a daily wage of 2,800 rupees (about $45 CAD).

The probe also uncovered that four floors of the building were leased in August 2025 for 105,000 rupees a month by Sudhanshu Lavnish and his associate Shubham Tyagi, who ran the facility under the name "Hostel Daze." The rent was notably low due to the building's poor condition.

The lease agreement contained unusual clauses absolving the PG operators of liability for any accidents, natural disasters, or personal injuries, while also barring parents from visiting their children on the premises.

Five people have been arrested in connection with the incident, including the property owner's son, Mahesh, contractor Sanoj Kumar, and operator Sudhanshu. The 81-year-old primary property owner, Hariram Gupta, and his wife have already been remanded to judicial custody.

Police are currently searching for the second PG operator, Shubham Tyagi, who remains at large. Meanwhile, the Municipal Corporation of Delhi (MCD) has launched a crackdown on illegal construction in the area.