FAIRFIELD (CBS-SF) — A 24-year-old woman has been arrested for allegedly causing the death of an infant boy she was babysitting at Travis Air Force Base, Fairfield police said.

Gina Nicole Bailey allegedly violently shook and dropped the 18-month-old boy, who was taken last Thursday to David Grant Medical Center from a home in the 100 block of Michigan Street on the base, according to police.

The baby had difficulty breathing and had to be placed on a ventilator. He was transferred Friday to UC Davis Medical Center in Sacramento, where he died despite no external signs of trauma.

Autopsy results and extensive interviews led investigators to determine the case was a homicide and the infant’s death was caused by a severe brain injury.

Investigators learned the baby was in the care of Bailey, a regular babysitter used by the family, who allegedly shook the baby and dropped him on the floor, according to police.

Bailey, a civilian resident on the base, was arrested at about 6 p.m. Tuesday and was booked into Solano County Jail on $750,000 bail.

Fairfield police and Air Force law enforcement personnel were continuing to investigate the case. No other information was immediately available.

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