Concern is mounting for a 57-year-old Markham woman who has been missing “under suspicious circumstances” since Thursday.

York Regional Police say officers responded to a missing person call at a wellness centre in the area of Woodbine Ave. and Steelcase Rd. – north of Steeles Ave. E. – around 5:30 p.m.

“Ying Zhang was last seen at the wellness centre at approximately 10:40 a.m.,” Const. James Dickson said in a statement released Saturday. “Her family contacted police after she failed to return home from her work.”

He said police and Zhang’s family are “concerned” for her well-being.

“This is out of character for her and the circumstances surrounding her disappearance are being treated as suspicious,” Dickson said.

Zhang, who is Chinese, is described as 5-foot-7, with a medium build, and straight, shoulder-length, black and grey hair.

She was last seen wearing blue scrubs and a jade bracelet on her left hand.

Anyone with information with information regarding Zhang’s whereabouts is urged to call police at 1-866-876-5423, ext. 7865, or Crime Stoppers at 1-800-222-TIPS (8477).