A charity working to stop illegal evictions has urged the Metropolitan police to give its officers better training after they failed to arrest a landlord who allegedly forced his way into a family’s home with a crowbar and tried to drag them down the stairs.

Roz Spencer of Safer Renting, an advice service for tenants backed by four London boroughs, said people were being evicted illegally every week in most British towns and cities, but the police nearly always failed to treat it as a crime. “We would like the police to understand that it is a criminal offence to kick someone out without a possession order,” she said. “Their job is to intervene when a crime has taken place.”

She said that she advised tenants threatened by their landlords to call the police, but had to warn them that the police may dismiss it as a civil matter. “But it is not a civil matter. It is a criminal offence to disregard the Protection from Eviction Act.”

Figures seen by the Observer show that the number of families contacting Citizens Advice about illegal evictions has increased by just over 40% since 2014, with nearly 2,000 families seeking assistance last year.

Elise Jones (not her real name) and her two sons were told by her landlord that they would have to leave their rented home in Chingford, north-east London, after Waltham Forest council discovered that the property was not registered under its licensing scheme.

Jones claimed her landlord did not serve her with a legal notice giving at least two months’ notice, and failed to obtain a court order for eviction. Instead, she said, he threatened to cut off the family’s electricity supply and attempted to force his way into their flat on three occasions. She also claimed that he and another man broke down the door of the property using a set of tools including a hammer and a crowbar.

Jones’s daughter, who was in the flat when the landlord broke in, said the family feared for their lives. “They grabbed my mum. They grabbed me and my sister. They were hitting my brother with a hammer. They kicked my mum on her belly several times. They dragged us down the stairs,” she claimed. “Oh my God – it was horrible. We didn’t know if we would see tomorrow.” However, when officers from Chingford police station turned up, the family claimed that they arrested neighbours of theirs who had come out to help them, instead of the landlord. “The police didn’t want to hear what we had to say – my neighbours got arrested for defending us,” she said.

The Met said the police aimed to remain impartial and only intervened where a criminal offence occurred or to prevent a breach of the peace. “Should an offence be alleged under the Protection from Eviction Act, the role of the officer attending is to compile a report for the local authority,” the force said in a statement. It added that the men accused of evicting the family were currently under investigation by Waltham Forest police.

Dave Hickling, chair of the Association of Tenancy Relations Officers, whose members enforce anti-eviction laws, said rogue landlords sometimes tried to escape council attention by throwing tenants out. “Local authorities are getting better at dealing with rogue landlords,” he said. “But landlords think the enforcement action will go away if they get rid of the tenants.”

He added: “The police need to be aware of the basics. It is a criminal offence to make your tenant leave unlawfully, be that through harassment or changing locks.”

Research by Shelter, the housing charity, suggests that in 2016 almost 50,000 renters had their belongings thrown out of their home, and the locks changed by their landlords. More than 200,000 renters had been harassed by their landlord and some 600,000 had their home entered by a landlord without permission.

In Numbers

64,000

renters reported that a landlord had cut off their utilities in the past year

200,000

tenants reported having been abused, threatened or harassed by a landlord

220,000

unique visits to Shelter’s advice pages for people having problems with a private landlord, over 12 months

Source: YouGov survey of 3,250 renters for Shelter