Authorities say 22-year-old Victor Montalvo and 21-year-old Maritza Lopez have been arraigned on charges including attempted murder.
They allegedly stole 19-year-old Alexander Herald's cell phone on a No. 4 train, then waved it at him at the Fordham Road station to taunt him.
When he tried to get it back, prosecutors say Montalvo repeatedly stabbed him.
Herald remains in critical condition.
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