Police in Zimbabwe say they have arrested at least 12 people in unrest over the firing of a popular Canadian doctor from a rural hospital in the impoverished northeast.

Witnesses said Friday hundreds of villagers demonstrated outside the hospital run by the Salvation Army to demand the reinstatement of Dr. Paul Thistle who has worked in the Chiweshe community medical facility, about 80 kilometers (50 miles) from Harare, for 16 years. A church vehicle was overturned and riot police fired tear gas to disperse protesters on Thursday.

Thistle, from Scarborough in Canada, has been given until Sept. 1 to leave his post.

Witnesses said Thistle had disagreements with superiors over hospital development projects, but community leaders want him to stay.