The death of a baby has lead to assault charges against an 18-year-old New Brighton man, the Staten Island Advance said.

Joshua Guzman has been arrested in connection with the death of his live-in girlfriend’s 14-month-old son. The child, Seth Azemi, died Wednesday, five days after being brought into the hospital.

On the morning of Oct. 7, Seth was found unconscious and unresponsive. He was in Guzman’s exclusive care at that point, the suspect told the court. Guzman said he picked up the child, and the toddler’s head and torso reportedly struck the bedroom wall, then the wooden door, as Guzman carried him out, court documents say.

Though police had not suspected assault initially, the medical examiner ultimately discovered two skull fractures.

Examiners still have not yet determined the cause of death, however. Complete tests will take six to eight weeks.