11/16/2014 01:37 EST | Updated 01/16/2015 05:59 EST

2 pedestrians, 2 motorists dead after 3 crashes in York Region

Two pedestrians and two motorists have died in a series of collisions across York Region since Saturday night.

Last night, a 70-year-old male pedestrian died after being struck at Yonge Street and Bond Crescent in Richmond Hill. Police say the incident is an apparent hit-and-run. Investigators are seeking a dark-coloured SUV.

At 12:30 a.m. on Sunday, police say a 36-year-old woman was struck and killed by a minivan on Yonge Street in Newmarket. A 37-year-old man has been charged with impaired driving causing death.

About two hours later, a head-on crash claimed the lives of two people near Bathurst Street and King Road. That collision remains under investigation.