The Yonkers girl suspected of fatally stabbing a New Rochelle High School classmate Wednesday has surrendered to police, according to authorities.

Police accuse Z'inah Brown, a 16-year-old from Yonkers, of stabbing New Rochelle's Valeree Schwab, also 16, in a fight near the school that rumbled through several fast food restaurants before culminating at Dunkin' Donuts.

Investigators say Brown and Schwab were among about a half dozen teens in the altercation, which began at the McDonald's on North Avenue around 12:30 p.m. Wednesday. 

At one point, authorities say Schwab used pepper spray against Brown. The fight spilled into a Subway restaurant and moved into Dunkin' Donuts, too. Brown eventually stabbed Schwab twice in the torso with a steak knife and fled the scene on foot, detectives say. Schwab later died at Jacobi Medical Center in the Bronx.

Brown now faces a charge of second-degree murder. She said nothing at her arraignment Thursday evening and is due back in court Jan. 17.

Her lawyer told reporters that "she's doing OK," and said his client's fate is now in the hands of the district attorney.

Police say Brown previously lived in New Rochelle and still attends high school there, despite moving to Yonkers. Police say at least five other teens were at the Dunkin' Donuts during the stabbing, but so far no one else is facing criminal charges.

Meanwhile, some New Rochelle High School students say their classmates should be careful who they associate with.

"If you get in the crowd with the wrong people, then it's going to be around you, and you'll feel unsafe," says Janitta Barrios. "You have to watch who you hang around with out there."

Police say they also investigated a rumored threat against the school related to the stabbing, but have minimized its importance.

New Rochelle Mayor Noam Bramson and Brian Osborn, the district's superintendent, say they increased security on campus.  They are also going to look at the district's policy of allowing students to leave campus for lunch. 

Osborn also says Schwab was absent from school the day of her death.