LONDON — Londoners are getting a warning about engaging in alcohol-fueled escapades, which can be disorderly at best or cause serious injuries and criminal behavior at worst.

People who repeatedly commit alcohol-related crimes will be forced to wear ankle tags that monitor their drinking by recording levels of alcohol in their sweat every half-hour, the mayor of London announced Thursday.

The yearlong initiative, which will be run in four London boroughs, authorizes courts to prohibit repeat offenders from drinking. If any trace of alcohol is detected, the “sobriety tag” will send an alert to the offender’s probation officer, and the person may be called back to court and face fines or sentencing.

The aim, in addition to reducing alcohol-related offenses, is to relieve strains on the criminal justice system, police forces and health services. Up to 150 offenders are to wear the tags 24 hours a day, the mayor’s office said.