EL DORADO, Kan. -- The search for answers in the disappearance of a Butler Community College student led authorities to Room 21 of the El Dorado Motel, where a manager reported an altercation may have occurred.

Authorities will not release details of the evidence they found Saturday in that room, but said they believe Emily Sander was the victim of violence.

Sander, 18, was last seen Friday at the Retreat, a bar east of El Dorado, leaving with Israel Mireles, 24. Her car was found the following day at the bar.

El Dorado Police Chief Tom Boren said Mireles is the last person known to be seen with Sander.

Police asked for the public's help in finding the teen.

"We need closure on this one, one way or another, and hopefully it's a good one," said her grandfather, Clement Sander.

Sander was described as 5 feet 3 inches, with brown hair and blue eyes. She was last seen wearing low-rider blue jeans, a "Don't Mess With Texas" T-shirt and skateboard-style tennis shoes. She has multiple tattoos and body piercings.

Her grandfather described her as independent, saying she had worked multiple jobs because she wanted to be out on her own.

Mireles worked at a restaurant that recently opened next to the motel where he had been living, Det. Justin Phillips said. The motel is a mile and a half from the bar where the teen was last seen.

Phillips said Mireles and the teen were "friendly together at the bar."

Police are looking for him and his 16-year-old girlfriend. KWCH in Wichita, Kan., identified her as Victoria Martens.

Mireles was described 5 feet 6 inches, weighing about 130 pounds. The two are believed to be traveling in a gray or green Ford Taurus rental car with the license plate XUJ 487.

Authorities said they don't believe Sander is traveling with them. On Monday, police said they tracked Mireles to Texas and want to find him before he crosses the Mexican border.

Bill Rinkenbaugh, vice president for student services at Butler Community College, said Sander is a freshman at the main campus in El Dorado. He said if her fellow students need counseling, it will be available through student services.