SAN ANTONIO (Reuters) - A 19-year-old central Texas mother has been charged with child endangerment for the deaths of her two daughters, ages 1 and 2, who were left in a car for about 15 hours, law enforcement officials said on Friday,

Amanda Hawkins, 19, and a 16-year-old male, who was not identified, brought the toddlers to a hospital in Kerrville on Wednesday and claimed Hawkins’ daughter collapsed after smelling flowers, Kerr County Sheriff Rusty Hierholzer told reporters.

The children were in grave condition and rushed to a better-equipped San Antonio hospital about 60 miles (100 kms) away, where they died on Thursday night, he said.

No lawyer was listed for Hawkins in online jail records.

“This is by far the most horrific case of child endangerment that I have seen in the 37 years I have been in law enforcement,” Hierholzer said.

The sheriff’s office suspects that Hawkins intentionally left the girls in a car while she was in a home from Tuesday evening until about noon on Wednesday near Kerrville.

Weather records show the temperatures ranged in that time from the low 70s (about 22 degrees Celsius) to the high 80s (about 31 degrees Celsius).

“Upon discovering the girls, the mother attempted to bathe them and did not immediately want to take the girls to the hospital because she did not want to get into trouble,” Hierholzer said, adding prosecutors were considering whether to change the charges against Hawkins to murder.