PLAINFIELD - Police arrested a man last night for allegedly beating his 3-month-old child in Plainfield.

Prosecutors say 34-year-old Michael Bell Jr. was arrested last night in Newark while attempting to flee the state on a bus.

The Union County Homicide Taskforce, the New Jersey Transit Police Department and the Amtrak Police Department worked together to arrest Bell near Penn Station.

The infant that Bell is accused of attacking remains in grave condition at Robert Wood University Hospital. Police say the baby suffered fractures and internal bleeding.

Bell was transported to the Union County Jail and ordered held without bail.

The Union County Prosecutor's Office says Bell has been charged with aggravated assault, although more criminal charges are expected.