Police Lt. Clinton Nichols says today that detectives are retracing Walker's activities in the hours before he was found injured a little after 7 a.m. Monday on a service street a block east of the Las Vegas Strip.
Police said Monday that Walker was hospitalized at Sunrise Hospital and Medical Center with "significant injuries."
Nichols says the 29-year-old Walker might be released from the hospital today.
Walker signed a six-year, $55 million deal with the Raiders after being released by the Denver Broncos in February.
A Raiders spokesman said the team was in the process of gathering information and had no further comment.