The contractor responsible for the fire alarms at Grenfell Tower is part of an ongoing fraud investigation by police and Hackney Council.

Fire safety equipment installed in Hackney residences between 2011 and 2014 by housing developer Lakehouse, and subcontractor Polyteck, was found to be defective. This included “incorrectly installed alarms and emergency lighting systems,” according to the council.

Some of the victims from Grenfell Tower said that the fire alarms were not working properly and did not go off during the June 14 blaze.

The installation of new fire and smoke alarms and emergency lighting was part of a £184 million property renovation scheme managed by Hackney Homes, the council’s former housing development company.

Ten people have been arrested after Hackney Council received allegations of “fraud and overcharging” by Lakehouse.

Scotland Yard said three men were arrested on suspicion of bribery and released on bail until November. The remaining five men and two women have been released from police custody but remain under investigation.

Hackney Mayor Philip Glanville urged councils to “carefully check” work carried out by Lakehouse and Polyteck in a letter to town hall chief executives on July 3.

Glanville said in the letter: “At all times, throughout this, our focus has been on the safety of our residents.

“We have no evidence to suggest that work carried out on contracts to other councils, by Lakehouse, or its subcontractor Polyteck, was in any way at fault, so we do not wish to cause undue alarm.

“However, we believe that as social landlords, after the Grenfell Tower tragedy we must share any information with each other that could potentially help to keep our residents safer.

“It is in this context that we are writing to you, so that if you have had fire safety works carried out by either of these contractors, you have a chance to check them carefully.”

The mayor also confirmed a criminal investigation is underway. “The issues in Hackney were uncovered during an ongoing fraud investigation and reported to the police immediately,” Glanville said.

A spokeswoman for Hackney Council said they are considering civil action against Lakehouse for overcharging throughout the entirety of its contract and for installing safety equipment that was later discovered to be defective.

The spokesperson said: “In 2014, Hackney Council’s Audit and Anti-Fraud team received allegations of fraud and overcharging relating to works carried out by Lakehouse.

“The Council’s primary focus was on the safety of residents, and it ensured, as a matter of priority, that these works were redone to the correct standard, and at the contractor’s own expense.

“Hackney Council immediately notified the police, and there is an ongoing criminal investigation. Hackney Homes was dissolved in 2016, with responsibility for housing management brought back in house.”

Lakehouse denied any misconduct in a statement last week:

“Lakehouse continues to co-operate with the Metropolitan Police and the investigation extends not only to certain former rogue employees of and subcontractors to Lakehouse, but also representatives of Hackney.

“There has never been any suggestion of wrongdoing on Lakehouse’s part, nor compromise in the interests of resident safety,” the statement reads.

Lakehouse also said claims of overcharging were false and that “works Hackney alleged were defective were determined to be fully due and payable.

“We continue to pursue Hackney for further sums which we are due contractually and for which they have refused to make payment to date.”

A spokesperson for subcontractor Polyteck told ELL that the company was not involved in the fire safety work at Grenfell Tower.