St. Catharines Fire Services has wrapped up its on-site investigation into two fires that damaged vacant buildings on Queen Street late last month.
Investigators, working with Niagara Regional Police, examined the December 26 fire at 9 Queen Street and a second blaze hours later at 17 Queen Street.
Although a combustible fuel source was found, the cause has been classified as undetermined.
Fire officials are asking anyone with information to contact police or Crime Stoppers and to report suspicious activity at vacant properties.
Cleanup is ongoing, Queen and William streets are fully reopened, but the sidewalk near the sites remains closed.
(Written by: DJ Blokzyl)