A cyberattack on the U.K.'s Police National Legal Database (PNLD) has compromised contact data of more than 100,000 police officers and other criminal justice professionals.

The intrusion was detected on Sunday, July 26, and was later claimed by the ExfilSquad data extortion group, which alleges it stole 135,000 contact records.

PNLD is an online legal resource service that has been used for more than 30 years by the 43 Home Office police forces in England and Wales, as well as the British Transport Police.

PNLD also operates ‘Ask the Police,’ a public-facing website with answers to hundreds of common policing and legal questions.

In a statement today, the service says that the breach exposed the full names, organizations, and email addresses of police officers, staff, criminal justice professionals, and government partners.