PEOPLE were forced to evacuate businesses and homes surrounding a Campbell Street business after a bomb threat was made via social media on Wednesday.

Police were alerted to the incident through The Guardian's Facebook page.

Swan Hill police Acting Senior Sergeant Darren Bull said police attended the incident at a service station about 11am.

"Police attended and evacuated the area -- local businesses and residential areas," Act-Snr-Sgt Bull said.

"We have conducted a thorough search of the area and no items of interest to us were located."

Act-Snr-Sgt Bull said police cordoned off the area while the evacuation process was in place.

Detours were in place at the intersections of Campbell and Werril streets, and McCallum and Curlewis streets, with the assistance of police directing traffic.

Act-Snr-Sgt Bull said the roads reopened at 2pm.

He said police investigations into the incident continued.

If anyone has any information, call Swan Hill police station on 5036 1600, Crime Stoppers on 1800 333 000, or the Police Assistance Line on 131 444.