The Brownsville Fire Department is warning residents that everyday items left inside a hot car can overheat, explode, and cause serious injuries.

The warning follows an incident last month when firefighters responded to a home after a portable battery charger left inside a hot car exploded.

The explosion damaged a woman's car and left her with second-degree burns. According to the fire department, the explosion occurred when an occupant attempted to connect a phone to the overheated charger.

"Because of the excessive heat inside the vehicle, the device exploded and caused pretty significant damage to the inside of the vehicle and some injuries to the patient," Public Information Officer Hector Martinez said.

Firefighters say temperatures inside a parked car with no air conditioning can jump about 50 degrees within an hour during the summer.

That's why the department says items like portable chargers and hand sanitizer should not be left inside a vehicle.

The department is also warning about squishy toys. Firefighters say if left inside a hot car, the toys can rupture and release superheated gel that can stick to skin and cause severe burns.

"Those gels, when they're heated up, can cause pretty significant burns because, unlike water or any other liquid, they're very viscous and stick to the skin and continue burning until they're cooled down," Martinez said.

Firefighters urge parents to check toys for any damage and follow the manufacturer's safety warnings.

If someone is burned, the department says to remove jewelry or loose clothing if possible. If material is stuck to the skin, do not try to pull it off.

Call 911 immediately if someone is burned or if something explodes inside a car.

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