A Texas man is accused of fracturing his 4-month-old child’s skull after becoming “frustrated,” officials said.

The child was admitted to a hospital in San Antonio on Dec. 13 with a “skull fracture and six rib fractures,” according to a Dec. 22 news release from the Bexar County Sheriff’s Office.

The child’s father, a 19-year-old, told deputies he fell down while carrying the infant, resulting in injuries.

But while reviewing the injuries, doctors determined they were in the process of healing, indicating they were not recent, officials said.

The “startling” discovery led Child Protective Services and Child Safe Investigators to look into the matter further.

An attorney for the father could not immediately be reached for comment by McClatchy News.

Upon interviewing the father, investigators learned the child’s injuries were not the result of a fall, but were intentional, officials said.

Sometime during September, the father said he became “frustrated” and started “striking and squeezing” the child, causing the injuries observed by doctors, officials said.

Additionally, when the child was crying in October, the father said he “squeezed him so tight until he heard a pop,” according to KSAT, citing an affidavit.

The father was arrested Dec. 20 and has been charged with injury to a child causing serious bodily injury, a first degree felony, officials said.

He was held on a bond of $300,000.

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