CAMBRIDGE — Cambridge Police released a "Looking to Identify" bulletin Monday for a man on an electric scooter who seriously injured a 9-year-old in a hit-and-run crash on Vassar Street and fled the scene.

The suspect, according to the department's own bulletin, is a white male seen wearing a teal green t-shirt and black shorts. His hair is up in a man bun style. He has what Cambridge Police describe as a face tattoo. He was operating an E-Scooter at the time of the crash.

The 9-year-old's injuries were described as serious.

The Cambridge Police Traffic Unit posted the bulletin with a color surveillance still — the suspect on the scooter, mid-ride, clearly visible from the shoulders up. Anyone who recognizes him, or has any information about the incident, is asked to call the Cambridge Police Traffic Unit at (617) 349-3300.

Vassar Street runs through MIT's campus, connecting the Kendall Square area to the Charles River side of the university. It's one of the most heavily used pedestrian and bicycle corridors in Cambridge, running past MIT dorms and academic buildings and along a shared bike-and-scooter lane. On a summer afternoon, it routinely carries students, faculty, families walking to the river, and children biking or scootering to camps and programs.

A hit-and-run on that corridor that leaves a 9-year-old with serious injuries — and a suspect fleeing on an e-scooter — is a serious matter for Cambridge families.

This is a developing story.