ACT OF EVIL: Man beats his mum to death two days after being released from Prison after 30-year murder sentence

Two days after completing a 30-year prison sentence for a 1984 murder conviction, a New Jersey man allegedly killed his 64-year-old mother. 
On Wednesday, Steven Pratt, 47, pleaded guilty to manslaughter, admitting his role in his mother's beating death, police say. 

A statement from prosecutors obtained by PEOPLE confirms Pratt, an Atlantic City resident who lived with his mother, repeatedly struck his mother Gwendolyn Pratt in the head the morning of Oct. 12, 2014. Police responded to the Pratt home that morning and found Gwendolyn's lifeless body inside. 

The statement says officers immediately took Pratt into custody and an autopsy later revealed the victim died from blunt force trauma to the head. 

Pratt faces 25 more years behind bars when he is sentenced within the next few months, police say. 

On Oct. 10, 2014, Pratt was released from a New Jersey prison, where he'd spent the previous three decades for the fatal shooting of Michael Anderson. 

When he was 15, Anderson caught Pratt smoking marijuana with friends and confronted the boy. 

During that incident, Pratt struck Anderson in the face with a lead pipe. After being hit, Anderson retreated, but hours later, Pratt knocked on his apartment's door. When he opened it, Pratt shot Anderson.