UPDATED, 6:20 p.m., with information from Waltham Police: The victim of the crash is in stable condition at Tufts Medical Center in Boston. 

The victim, a male, was walking north on on Lexington Street when he tried to cross the street by weaving between vehicles. He was not in a crosswalk. 

As he reached the southbound lane, a vehicle, driven by a 17 year-old Waltham man, struck the 15 year-old.

The victim was on his way home from school. 

Police are investigating the incident, but say speed or impairment don't appear to be a factor in the crash.

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UPDATED, 5:13 p.m. w/information from Waltham Public Schools Superintendent: Waltham Public Schools Superitendent Susan Nicholson just confirmed to Patch that the victim is a Kennedy Middle School student. His condition is not known at the moment. 

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UPDATED, 5 p.m.: The victim of the crash is 15 years-old and sustained serious injuries, including a head injury, according to Waltham Fire Lt. Michael Murphy.

According to WCVB-TV, the victim is a student at Kennedy Middle School and a 17 year-old was allegedly driving wht minivan that struck the victim.

Authorities responded to the scene at 2:45 p.m. after receiving reports of the accident and firefighters arrived one minute later, according to Murphy. The victim was taken by ambulance to Falzone Memorial Park on Trapelo Road where a MedFlight helicopter was waiting for him. At 3:35 p.m., the helicopter departed for Tufts Medical Center, where the victim remains hospitalized. 

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Authorities are responding to reports of a child being struck by a vehicle at 770 Lexington Street, according to scanner and Twitter reports.

A MedFlight helicopter has been requested to land at Falzone Memorial Park on Trapelo Road, according to scanner reports. 

Stay tuned to Waltham Patch for updates to this story.