Colorado authorities are searching for a man wanted on a murder charge in Illinois who escaped while being transported from Las Vegas.

Police say 37-year-old Turhan Robinson escaped from a private inmate-transport service at a truck stop in the Denver suburb of Wheat Ridge early Friday.

Jim Lorentz, a Wheat Ridge police division chief, says investigators believe Robinson was shackled but officers are trying to confirm whether that was the case.

Lorentz says Robinson had been arrested in Las Vegas, but he did not know where in Illinois he was being taken.

Officers and a tracking dog were looking for Robinson.