The scene of a late Sunday/early Monday standoff with law enforcement had ended by Monday morning.

Law enforcement officers, including members of the Natrona County Special Response Team, were using a loudspeaker to urge a person or persons in north  Casper to leave a trailer at 3:30 a.m. Monday after a nearly four-hour search.

"Come on out, hands up, hands up and empty," a negotiator kept repeating to a person they believed to be inside a trailer.

Negotiators implored the man to come out and talk, or call 911 or a general number for dispatch. They said they weren't going anywhere.

The person or persons inside did not respond to any of the demands.

The Sheriff's Office, Casper Police and other agencies responded to the 1100 block on Burlington Avenue about a report of a shot or shots fired about 11:30 p.m. Sunday. Burlington Avenue was blocked for several blocks east of North Jackson Street.

Law enforcement officers were looking for a person of interest -- male, in his mid-50s, wearing shorts and a T-Shirt either in a trailer or nearby.

Detective Tiffany Elhart of the Casper Police Department told K2 Radio News that there were no immediate reports of injuries in connection with the shots fired call, which police received about 10:30 p.m. Sunday.

Elhart said police were looking for a person of interest, who she described as a male in his mid-fifties. A person of interest is not necessarily suspected of committing any crime.

While officers believed the person of interest was in the trailer, Elhart said they were not certain of that.

At one point, two SRT officers and a K9 officer and dog walked west on Burlington Avenue and turned north on North McKinley Street where the underpass is being renovated. Those officers later returned to the 1100 block of Burlington Avenue.

After an initial search, SRT officers armed with long guns deployed an armored vehicle in front of a trailer with a camper in front.

About 2:15 a.m., officers went to a trailer next to the one where the person of interest apparently was. Officers knocked on the door, broke windows, used tear gas and cleared this trailer.

Monday morning, there was no law enforcement presence, nor was there any crime scene tape or indications of an ongoing investigation.