Swift Current RCMP say a semi hauling hydrochloric acid crashed north of the city on Friday morning.
The crash happened at about 10:30 a.m. CST on Highway 4 about five kilometers north of Stewart Valley.
RCMP said the semi was carrying 39 tonnes of the acid and police are not sure how much spilled. A hazardous materials team has been dispatched from Alberta.
A perimeter has been set up around the site and police say Highway 4 near Stewart Valley will be blocked until further notice.