A Texas mother charged in the deaths of her two children told authorities she saw them before going to sleep, then woke to find the front door open and discovered them unresponsive in her hot car.

Investigators in Bexar County have said her account contains inconsistencies.

Deputies respond to San Antonio home

Tiona Lasaisha Islar, 28, has been charged with two counts of causing serious bodily injury or death to a child, according to the Bexar County Sheriff's Office.

Her bond was set at $300,000 after her two children — a 6-year-old son and 3-year-old daughter — were pronounced dead on Saturday afternoon.

Mother describes waking to open door

Deputies responded Saturday afternoon to a report of injury to a child in the 7000 block of Chancery Gate, on the far west side of San Antonio.  

Islar told authorities that she last saw the children around 8 a.m. before dozing off and awoke at about 3 p.m. to find the front door open. She then said she located the children, who weren't responding, in her car.

Deputies arrived on scene at around 3:30 p.m. and attempted life-saving measures after she said she had brought the children into the house. Her two children were pronounced dead at 3:38 p.m., the sheriff's office said.

Medical examiner reviewing cause of death

Bexar County's medical examiner will determine the cause and manner of death, according to the sheriff's office.

The investigation is continuing.

Anyone with information or security footage is asked to contact the Bexar County Sheriff's Office at (210) 335-6000 or email BCSOTIPS@bexar.org.