A Rotterdam man is under arrest, accused of causing serious brain injuries to his two-month-old son.

Tristian Tinney, 21, is behind bars after police say he shook and abused his two month old son inside their Phillip Street home in Rotterdam on Saturday. Police say the child suffered a brain injury and fractured ribs.

"We believe Mr. Tinney acted alone," said Lt. Bill Male of the Rotterdam Police Department.

According to police, their investigation started after the mother took the child to Albany Medical Center Sunday afternoon after she notice her son was having a seizure. Doctors ran tests and a CAT scan on the two-month-old boy.

"That's where they realized the child had suffered some injuries suggestive of abuse," Male said.

Police say Child Protective Services was called in. Police were then notified and started interviewing family members and caretakers of the baby.

"Based on our interviews and evidence, when matched with the medical records of the injuries, we were able to arrest Mr. Tinney," Male said.

Tinney has been charged with assault and reckless assault of a child. Police say evidences show the injuries were a result of an intentional act.

"We do get some abuse cases over the course of the year, but nothing as severe as these injuries," Male said.

According to police, the baby is currently in stable but critical condition at Albany Medical Center.

Spectrum News spoke with a resident at the Phillip Street home on Tuesday. She says they haven't had contact with Tinney since Sunday and they're only focusing on the health of the baby right now.

Tinney was arraigned in Rotterdam town court and sent to the Schenectady County jail on $50,000 cash bail. He's due back in court Thursday afternoon.