Images from a school changing room have been discovered at the house of a deputy head teacher who was found dead earlier this month in the UK.

Essex Police began an investigation on September 9th into allegations that Martin Goldberg (46) had images of naked teenage boys on his computer and had bought material from abroad.

He was not arrested at the time because police said there was insufficient evidence, but when officers returned to his home in Shoeburyness the next day following concerns for his welfare, his body was found.

Officers continuing their investigation found the photos on a camera hidden inside a bag.

Essex Police said the camera had been used to film male children undressing at Thorpe Hall School, in Southend, in the changing rooms at Southend Leisure and Tennis Centre swimming pool and two other unidentified locations.

In total 75 images in the school's male changing rooms, which are classified as indecent, were recovered. There were a further 465 images from the swimming pool and 38 from the other two locations.

"These are criminal offences of voyeurism under the Sexual Offences Act 2003," a spokesman said.

Specialist detectives have identified four of the children and their parents have been informed. Officers believe the images date from 2000 onwards and appear to be of boys aged from nine to 12.

Just over 1,000 still and moving images have been recovered from Goldberg's computer, although there was evidence he had tried to delete content.

Police added that they have found no evidence to suggest that Goldberg had any inappropriate physical contact with the children.

The force said Thorpe Hall School has cooperated with their investigation and there is no reason to believe the teacher shared the images with anyone else.

Anne Jones, Southend-on-Sea Council's executive councillor for Children and Learning, said: "We have been working very closely with Essex Police and Thorpe Hall School since this matter was drawn to our attention earlier this month.

"As a parent myself, I can understand how upsetting this must be to all those concerned."

Nick Alston, the county's police and crime commissioner, said there were indications that mistakes may have been made in the case.

He added that the original investigation had been launched after police in Toronto, Canada, contacted Essex Police in November 2013 with information suggesting that Goldberg had bought videos of naked boys several years ago.

As a result of this delay, the case has been referred to the UK Independent Police Complaints Commission (IPCC).

At a press conference, Chief Superintendent Luke Collison of Southend Police refused to confirm there was a delay or discuss the issue because of the IPCC's involvement.

Mr Goldberg's death is not being treated as suspicious and the matter has been passed to the coroner.

A statement from the school at the time of his death said: "Mr Goldberg was a fantastic maths teacher who inspired countless young Thorpe Hallians over the last 23 years to strive to do their best and achieve amazing things."