An infant boy is dead after being accidentally strangled by a car seat seatbelt while sleeping in a walk-in closet at a babysitter's home, according to law enforcement officials.

Police in Fort Worth, Texas say the bottom strap of the car seat was not properly connected and the nine-month-old slid down the car seat, was caught in the chest buckle that was fastened and suffocated. Police say the babysitter left the baby to sleep in the closet of the master bedroom and discovered him dead two hours later.

There were 10 or 11 children inside the babysitter's home when the little boy died and the location was not licensed for child care operation. The Tarrant County Medical Examiner's Office confirmed the infant's death as accidental but the case is still being investigated by CPS and Child Care Licensing. The babysitter is currently not facing any charges.

Sadly, this isn't the first time a child has died as the result of sleeping in a car seat while not properly fastened. It happens more than it should.

In April of 2016, an 11-month-old girl in Indiana died after a child care worker incorrectly strapped her to an infant car seat. She was strangled in the same manner as the infant boy in Fort Worth.

In June, a 17-month-old also from in Indiana was declared brain-dead after he was improperly fastened into a car seat by a caregiver. Doctors believed the baby was without oxygen for at least 30 minutes after he was strangled by the seat belt. An 11-week-old Oklahoma baby died in 2015 after a child care worker put him down in a car seat for a nap and he slipped down and suffocated. He was still too little to lift up his head.

It's commonly understood, properly securing children in car seats is crucial for keeping them safe during car rides, especially in case of an accident. Children often fall asleep in their car seats and some parents even take their kids on car rides to help put them to sleep. It may be tempting to leave a child asleep in their car seat to avoid waking them.

But studies warn against leaving babies to nap in car seats.

The American Academy of Pediatrics recommends that infants sleep on their back on a firm mattress, without loose bedding.

In April of 2015, a study was published in the Journal of Pediatrics warning about the dangers of allowing babies to sleep in carrying devices, such as car seats.

The researchers analyzed records for 47 deaths associated with sitting and carrying devices. All but one were attributed to asphyxia, either positional or strangulation. Two-thirds of the cases involved car seats and strangulation from straps accounted for 52 percent of the car seat deaths.

The study notes, when a child is properly strapped and positioned into a car seat, it poses little risk from a suffocation injury or death.

However, parents and caregivers should never use car seats for unsupervised sleeping or leave children sitting for long periods of time without being checked on.