ST. GEORGE, Utah – Police in Utah continued their search Monday for a missing 5-year-old girl, alongside officials from the FBI and state law enforcement agencies.

Elizabeth Jessica Shelley was last seen around 2 a.m. Saturday and reported missing approximately 8 hours later, according to the Logan Police Department.

Officials said the girl may have been with her 21-year-old uncle, Alex Whipple, who is now in police custody.

Whipple was booked into Cache County jail in connection with a warrant out of Salt Lake County regarding a failure to comply with probation, police said.

Logan police described the 21-year-old as the "main suspect" in a Facebook post on Sunday.

Law enforcement personnel conducted searches throughout Saturday night and into Sunday morning. More than 200 people were participating in the search as of Sunday evening, Logan police said.

The search for the girl stretched into a third day on Monday, with the child's family saying they are overwhelmed, scared and saddened by her disappearance.

Jill Parker, a victim advocate with the Cache County Attorney's Office, read the family's statement at a brief news conference Monday in Logan

Authorities advised residents in the search area to monitor their home security systems for suspicious activity.

"Any residents in the area between 300 South to 100 North and 300 West to 600 West that have video surveillance, including smart doorbells please check your videos and cameras specifically for the hours between 2 a.m. and noon on Saturday, May 25, 2019," Logan police said in a Facebook post.

"If anything is found, please don’t touch it and call dispatch immediately," police officials said.