The hawk was found near the cross road of Gilbert Street, between St. Jude's School and the Joyce Funeral Home, just before 6 a.m. this morning.
A passerby called police, who dispatched an officer to stand with the bird while environmental police were called to the scene.
Environmental officials then transported the hawk in a box to the police station.
The hawk was subsequently taken to the School of Veterinary Medicine at Tufts University for treatment, said Waltham Sgt. Dennis Deveney, who tweeted a picture of the bird today.
Deveney said police could not tell whether the bird was injured or sick.
"Hawks are common in Waltham - we have a lot of them, but I’ve never seen one in that shape, especially hanging out in the middle of the street," he said. "It’s uncommon to see them like that. They’re strong birds."
Jaclyn Reiss can be reached at firstname.lastname@example.org