The order followed a massive blaze in the city's downtown
The shelter in place order was finally lifted last night for residents living in the Yates Street neighbourhood.
The order was put into effect yesterday after billowing smoke from a massive fire in downtown St. Catharines enveloped the area.
Crews spent hours yesterday battling the flames that gutted the site of the old Welland House Hotel on Ontario and King.
Despite the building being gutted, St Catharines council went ahead with a pre planned debate last night giving the site an historical designation.
The Welland House Hotel was built in the mid 1800's and was popular for its healing waters, the underground saline spring waters underneath the hotel that were believed to have medical and curative powers.
A cause of the blaze is unknown.
Police and the Ontario's Fire Marshall's Office are continuing their investigation.
NRP say the scene is expected to be held for a significant amount of time as the investigation continues.
Anyone with information is asked to contact police at 905-688-4111, ext. 1008429.

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