Classified police papers linked to gang-related crime stolen from off-duty officer's car

West Midlands Police said the data loss is being investigated by its professional standards department and an investigation has also been launched by the Information Commissioner’s Office.

According to a formal letter, which has been sent to those affected, the property stolen included police documentation and a note book containing names, addresses, vehicles and dates of birth for a number of people linked to criminality and gangs within the Walsall area.

Police chiefs have confirmed the information contained details of people "assessed as being involved in, or vulnerable to, gang-related activities", but say they do not believe the loss has directly put anyone at risk.

It is understood the items were taken from a locked vehicle in the Walsall area on September 1.

Four men have since been arrested.

Chief Superintendent Ian Green, head of the intelligence team at West Midlands Police, said that following the theft an investigation had immediately been launched to determine any threat and risk posed to the community.

He said: "On September 1, items containing police intelligence were stolen from a vehicle belonging to an off-duty officer in Walsall.

“Three men have been arrested regarding the theft. They have been released on police bail while the investigation continues.

“ A fourth man was arrested on Friday morning and remains in custody."

He added: “A debrief was carried out with the officer involved so we could quickly determine what information was contained in the items stolen.

"The information contained details of people assessed as being involved in, or vulnerable to, gang-related activities.

“Once this review was carried out we undertook a comprehensive intelligence assessment to understand if any of this information would pose a risk to any individuals.

“We are visiting and sending formal letters to the people concerned, notifying them of the theft and offering support. We continue to monitor any potential risks within our communities and put the appropriate safeguarding in place."

Chief Superintendent Green added: “We do not believe that the loss of this information has directly put anyone at risk and we’ve been in contact with those who’ve had any concerns.

“The data loss is being investigated by our professional standards department and we referred it to the Information Commissioner’s Office (ICO).

"The ICO investigation is ongoing and we will welcome the findings of the ICO report once completed and will take any recommendations on board.

“We manage highly sensitive information every day, which is vital in our fight against crime.”