A Brooklyn man has been charged after a 3-year-old boy he was watching suffered head trauma inside a home.

Salvatore Lucchesse, 24, was charged with assault and endangering the welfare of a child Wednesday. Police say Lucchesse was watching his girlfriend's son, Jaden, when he told police the child slipped in the tub and hit his head.

Officers say they were called to a home on West Fifth Street on Monday in Gravesend and found the unconscious boy. He was rushed to a hospital with severe internal injuries, and is listed in critical condition and on life support.

Lucchesse was taken in for questioning and admitted to calling 911, but also told officers he attempted to give the child CPR. The mother of the child, Raven Andrea Jordon-Alsina, was also taken in for questioning, but later released.

Lucchesse has six prior arrests, and officers say they are sealed from the record.

Jaden's biological grandfather, Ali Aliyev, says his son, Guseyn Aliyev, Jaden's father, broke up with Raven two or three years ago but still pays child support. Aliyev says his son never knew of any abuse by Lucchessee prior to the incident. 

Aliyev says Guseyn saw his son this week in the hospital and says he is clinging to life.

The New York City Department of Investigation commissioner says his team will be investigating ACS's handling of the incident.

According to police, a few days before the boy was found unconscious, someone called ACS about possible abuse in the family, but gave the wrong address and ACS did not follow up.

A spokesperson for ACS said in a statement, "The New York City Administration for Children Services is saddened by this upsetting news. We are investigating the circumstances that led to this incident."

The organization added it could not comment any further on the case.