BOSTON — Police were called to Commonwealth Avenue in the early hours of Monday morning after a 911 caller claimed he was punched in the face by someone “in the bike lane.”

The bizarre pre-dawn altercation unfolded around 3:26 a.m. near 370 Commonwealth Avenue, a stretch of road nestled between Back Bay and Boston University that’s no stranger to late-night drama. According to scanner audio reviewed by Mass Daily News, the caller said he had been struck during a dispute with someone in or near the bike lane.

Boston Police referred to it as an “A&B in progress” — shorthand for assault and battery. Both parties were reportedly still at the scene when officers arrived.

Just minutes later, a second call came in describing an “unconfirmed incident” at 370 Commonwealth Ave, adding to the confusion about what exactly sparked the face-punching chaos.

While details remain murky, the scuffle appears to be the latest in a string of oddball confrontations linked to Boston’s growing network of protected bike lanes — a pet project of Mayor Michelle Wu that’s drawn praise from progressives and frustration from everyone else.

No arrests have been announced as of publication, and Boston Police have not released further information.

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