A bug in the web app has exposed details of more than half a million Neighborhood Watch members

Neighborhood Alert, a members-only messaging app in Britain, leaked sensitive user data to anyone who would look, experts have revealed.

In Britain, citizens can form neighborhood watch groups, which have their authorized administrators and other members. To communicate, members can use various apps, including Neighborhood Alert, according to a report from The register supported by national and regional local authorities, and had more than half a million members.