PULLMAN -- Whitman County investigators continue to sift through evidence and interview people as they work to piece together how a 23-year-old WSU alumnus ended up bloody and unconscious lying on the side of a remote section of road earlier this week.

The Whitman County Sheriff's Office believes Kristen Grindley either fell from a moving vehicle or was hit by one while on Pullman-Albion Road. Sheriff Brett Myers says several people that know Kristen have been questioned including her boyfriend. A search warrant was issued allowing investigators to search Kristen's house on Northeast Illinois off Stadium Way.

Sheriff Myers also confirmed a search warrant was issued allowing investigators to take a look at her boyfriend's truck while a neighbor said they saw a red Chevy truck being towed from Kristen’s home. The sheriff added that alcohol may have been a factor in the incident.

“Based on information we've been able to obtain through interviews we believe there was alcohol involved … that she was drinking,” Sheriff Myers said.

Grindley remains unconscious and in critical condition at Sacred Heart Medical Center in Spokane though her condition is improving.