This story has been updated.
GREENBURGH, N.Y. -- An Edgemont High School junior who ran away from her home Friday was last seen in a surveillance video entering a southbound Scarsdale Metro-North train at approximately 10:18 p.m. Friday, Greenburgh Police said.
With the help of MTA Police, Greenburgh Police are attempting to determine which stop she may have disembarked, Greenburgh Police Captain Brian J. Ryan said.
Greenburgh Police Chief Chris McNerney said Christine (Ji Woo) Kang, 16, left her home at 112 Robin Hill Road in the Scarsdale section of Greenburgh about 8:30 p.m. on Friday, Jan. 2 after a disagreement with a parent.
She was classified as "an endangered missing juvenile" on Monday due to falling temperatures.
During a news conference at Greenburgh Police headquarters on Monday, McNerney described the "minor argument" as "inconsequential" to the investigation.
The search for Christine, which is continuing, includes helicopters and canines and was expanded to the woods behind Edgemont High School.
The girl has run away several times before, but always returned after a couple hours, according to Ryan, who is commanding officer of Greenburgh's Detective Division.
Christine moved from Connecticut to Scarsdale with her parents and a sibling about a year ago, police said. Greenwich police are assisting in the search, in case she returned to Connecticut, Ryan said.
McNerney said there is heightened concern about the girl's safety because she left home without a coat. But there is "no reason to believe the community is at risk,'' McNerney said. "Now, we're obviously concerned because of the (winter cold) elements. . . That's why we classified her as endangered."
Police said Christine did not show up for school Monday morning.
A search of her Scarsdale home, police K9 search and neighborhood search were all conducted over the weekend with negative results, police said.
Police have expanded the search to the surrounding area including an aerial search with the assistance of the Westchester County Police Aviation Unit.
Electronic equipment including computers also have been searched for leads on the girl's possible whereabouts, McNerney told reporters.
"Nothing has been ruled out and we are considering every option at this point,'' McNerney said.
Christine was last seen boarding the Metro-North train toward New York City wearing a green pajama top and light colored pajama bottoms and Uggs boots. She is described as 5’6” tall and weighing 120 lbs.
The switchboard number at Greenburgh Police headquarters changed on Monday to (914) 989-1700. People with any information on Christine's whereabouts are asked to call this number.
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