NEW YORK (NewsNation) — A man charged with last month’s mass shooting in a New York subway, one of the most violent attacks in the history of the city’s transit system, is expected to enter a not guilty plea in Brooklyn federal court on Friday.

Frank James, 62, is scheduled to be arraigned at 12 p.m. EST on charges related to the April 12 gunfire and smoke bomb attack that injured 23 people. His lawyer, Mia Eisner-Grynberg from the Federal Defenders of New York, did not respond to requests for comment.

A total of 10 people were shot, and dozens were injured after James allegedly filled a subway train with smoke and unleashed gunfire as a train was pulling into the 36th Street station in Brooklyn’s Sunset Park neighborhood. Thirteen others were injured. No one was killed.

The motive for the attack remains unclear.

James is accused of using a dangerous weapon with the intent to cause death or serious injury. If convicted, he would face up to life in prison.

Reuters contributed to this report.