A Plainfield man has been charged with first-degree murder for allegedly severely beating his 3-month-old child to death.

Michael Bell (Union County Prosecutor's Office)

The charges against Michael Bell, initially charged with aggravated assault  by the Union County Prosecutors Office for severely beating his son Zino Bell on Friday night, were  upgraded following the infant's death on Monday.

Bell fled his Lee Place home after the beating incident and was found at Newark Penn Station on Saturday night trying to board a bus headed out to Iowa.  He is still being held at the Union County Jail without bail.

Bell will make his first court appearance on Friday in Union County Superior Court.

Plainfield police responded late Friday night and found the infant suffering from fractures and internal bleeding. He never recovered from his injuries.

The Associated Press contributed to this story.