Authorities are looking for a man who may have sexually assaulted a 14-year-old girl after she got off a school bus Nov. 5 in the Fern Valley area of northwestern Dawson County.

Dawson County Sheriff's Lt. Tony Wooten said the teenager reported she saw an unknown white man in a field off Hwy. 136 as she walked toward her house from the bus stop about 4 p.m. that day.

Wooten said the teen described the suspect as a white man in his 40s with long, black hair and a closely shaven beard. He was last seen wearing a black shirt with buttons and blue jeans in the Fern Valley area.

"The man entered the home from a back door of the residence and allegedly raped the teen," Wooten said.

A school counselor alerted authorities to the incident Thursday.

An investigator spent Thursday night attempting to gather evidence of the alleged assault.

"At this point, attempts to obtain physical evidence have been unsuccessful," Wooten said.

Sheriff's deputies have increased patrols before and after school at bus stops, according to authorities.

"We have also placed several deputies and school resource officers in the area where the alleged incident occurred," Wooten said.

School Superintendent Keith Porter prepared a message to notify parents this afternoon through the school's computerized phone system. He also sent letters home with students.

"The sheriff's department has been carrying out their investigation," Porter said. "Our role has been to try to inform parents regarding the allegations in a timely manner."

Wooten said the sheriff's office "has worked closely with the school system to make parents aware of the details we have just learned."

The case remains under investigation. Anyone with information should call 911.