Mumbai: Maharashtra chief minister Devendra Fadnavis told the legislative assembly on Wednesday that the prima facie reason for the collapse of a building in Mumbai’s northern suburb of Ghatkopar was structural damage to its beams and pillars caused by Sunil Sitap, proprietor of a nursing home on the ground floor of the building. Fadnavis, who ordered an inquiry into the accident on Tuesday, said if the probe confirms this, strict action would be taken, including prosecution for culpable homicide. The chief minister, who also holds the urban development portfolio, was responding to an opposition-sponsored adjournment motion on the incident.

The four-storey residential building named Sai Siddhi, built in 1983, collapsed on Tuesday morning. The accident had claimed 17 lives till Wednesday morning.

Survivors and local residents have accused Shiv Sena functionary Sitap of making structural changes to his nursing home without seeking the necessary permissions from Brihanmumbai Municipal Corporation (BMC).

Mumbai police arrested Sitap on Wednesday morning for negligence. He was produced in a local court, where he pleaded not guilty and claimed that he had not carried out any structural changes to the building. He has been remanded to police custody till 2 August.

Apart from the probe ordered by Fadnavis which will submit a report in 15 days, municipal commissioner Ajoy Mehta has appointed a civic officials’ committee to investigate and submit a report. Fadnavis has vowed the “strictest possible action against the culprits".

The Bharatiya Janata Party has picked on the opportunity to target the Shiv Sena-ruled BMC. The alleged involvement of a Shiv Sena functionary has provided further ammunition to BJP and other parties.

Since 2014, when BJP formed the government at the centre and later in the state, its ally Shiv Sena has rarely spared an opportunity to take target Prime Minister Narendra Modi and the state government. In particular, Sena has been critical of the central government’s demonetization move and its policy on Kashmir. Sena was also at the forefront of an agitation to demand a farm loan waiver. After the waiver was announced in June, the party criticized the government for its eligibility conditions. After Sena won 84 seats to BJP’s 82 in BMC elections held in February this year, Fadnavis had said that BJP will not be a part of government at BMC but its corporators would work as “civic sentinels or watchdogs" and object to any wrongdoings.

BJP legislator Atul Bhatkhalkar, without naming Sitap, said the “person responsible for the building collapse" must be held accountable by the party he belonged to. Referring to Shiv Sena legislator Sunil Prabhu’s claim that there was no online or written complaint against the alleged irregularities in the building, Bhatkhalkar said this could be because the residents were afraid of taking on the Sena functionary.

Senior BJP legislator Yogesh Sagar also demanded action against civic officials responsible.

Last week, Mumbai BJP supported radio jockey Malishka Mendonsa who released a music video mocking BMC for its inept civic governance during the monsoon and the potholes on Mumbai roads. Mumbai BJP chief Ashish Shelar had tweeted in support of Mendonsa saying she had lent her voice to Mumbai citizens facing troubles every day. Shelar, who led BJP campaign in BMC polls with Fadnavis, has been particularly scathing in his criticism of the Sena’s civic governance.