Prosecutors charged a 30-year-old Casper man with first-degree sexual assault Monday in Natrona County Circuit Court.

Juan Marcos Loya, of 446 N. Lowell St., made his initial court appearance before Circuit Judge Michael Patchen. His bond was set at $30,000.

Assistant District Attorney Mike Schafer, in recommending the bond, described Loya's alleged crime as "very serious." He did not elaborate and state law prevented the release of court documents related to the case.

First-degree sexual assault carries a maximum penalty of 50 years in prison.

When asked by Patchen if he had anything to say, Loya, dressed in a county-issue orange uniform and with his hands and ankles shackled, shook his head no. He remained jailed Monday evening.

Casper police arrested Loya about 9 a.m. Saturday after taking him into custody at Motel 6 earlier in the morning.

Police say the alleged victim, while in the hotel room with Loya, used her cellular telephone to send a text message to another person and report the sexual assault. That person called police about 6 a.m. and reported the crime, Sgt. Steve Schulz said.

The Star-Tribune does not identify alleged victims of sex crimes.

When officers arrived, they found Loya and the victim, an adult, in the hotel room. Officers interviewed Loya at the police station before booking him into Natrona County Detention Center.

In court Monday, Loya claimed to be employed at the Dave Johnston Power Plant in Glenrock. Through an interpreter, he told the court he has lived in Casper for roughly four months after moving from Salt Lake City.

Reach crime reporter William Browning at (307) 266-0534 or at william.browning@trib.com.