The crash occurred around 5 p.m. on East Main Street at Quintard Terrace in Stamford, said Sgt. Andrew Gallagher.
During the crash, the 2001 Chevrolet Venture van was traveling eastbound on East Main Street turning left onto Quintard Terrace, when it collided with the 2007 Suzuki GSXR 75 motorcycle traveling westbound, Gallagher said.
"Initial indications are that the motorcycle was traveling at an excessive speed," Gallagher said.
The van was being driven by a 44-year-old Stamford man. Both men were transported by ambulance to Stamford Hospital where the motorcyclist was admitted with life-threatening injuries, Gallagher added.
The van operator was treated and released.
The motorcycle driver was wearing a helmet, Gallagher said.
Any witnesses or anyone with information regarding the crash, are asked to contact C.A.R.S. at 203-977-4712.
The collision is being investigated by Officer Jeffrey Booth and Sgt. Gallagher.
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