Delta Police Sgt. Ciaran Feenan says the 43-year-old woman was critically injured when she was thrown by her horse at around 8:40 p.m. Wednesday night.
UPDATE: The woman killed in the horseback riding accident has been identified as Roseann Guerin, 43, of Ladner, The Province reports.
He says the woman and her 18-year-old daughter were riding through the rural Ladner neighbourhood south of Vancouver when the victim was thrown as her horse galloped away after being spooked by a dog.
The teen's horse then followed the first animal but was unable to jump a muddy ditch and both the teen and the second horse tumbled into the muck.
As rescuers rushed to perform CPR on the injured woman, others helped the teen out of the ditch and firefighters pulled her horse to safety.
Feenan says both mother and daughter were taken to hospital where the mother was pronounced dead and the girl was treated for scrapes to her face and bruising to her leg.
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