An aide to pope Francis has shimmied down a Rome manhole in order to restore electricity for hundreds of homeless people living in an unused state-owned building.

Cardinal Konrad Krajewski broke a police seal to turn the electricity back on on Saturday evening in the building where 450 people, including about 100 children, had been living without lights or hot water since 6 May, according to Italian news reports

“I intervened personally to turn the meter back on. It was a gesture of desperation. There were over 400 people without electricity, families and children,” Krajewski, who carries out acts of charity in the name of the pope, told ANSA news agency.

The cardinal “was fully aware of the possible legal consequences, and acted in the conviction that it was necessary to do it for the good of those families,” sources close to the Vatican’s alms office told Adnkronos news agency.

Matteo Salvini, Italy’s interior minister and leader of the far-right League party, said he hoped the papal aide would pay overdue electricity bill, estimated at €300,000 (£260,000).

Sister Adriana Domenici, who works with the homeless, told Italian broadcaster RaiNews24 that after the building’s electricity was cut off on 6 May, she called Krajewski for help.

She said that when utility workers returned to disconnect power again, they found a note from Krajewski and left the electricity running.

Pope Francis has transformed Krajewski’s centuries-old job – that of Vatican almoner – into a hands-on, door-to-door charitable mission.

Krajewski has just returned from the Greek island of Lesbos, where he travelled to deliver financial donations to projects helping refugees and assure both those living in tent camps and local residents that the pope has not forgotten about them.

Associated Press and Agence France-Presse contributed to this report