A Dallas-area mother will face capital murder charges after strangling her two children, killing her 5-year-son and leaving her 2-year-old daughter in critical condition in a Texas hospital, police officials said Tuesday.

Saiqa Akhter called 911 in Irving, Texas, Monday night and said she had done "something terrible" to her children. When police officers arrived at her home, they performed CPR on the boy, Zain, and his sister Faryaal.

"The older child — the boy — he was pronounced [dead] last night at the hospital," while his sister was still listed in critical condition as of this morning, said Officer David Tull, a police spokesman.

Akhter will be arraigned on a capital murder charge Tuesday and is sitting in the Irving Police Department's jail.

The Dallas Morning News says Akhter was the only adult at the apartment but that her husband was later seen leaving the police headquarters.

The Associated Press contributed to this report.

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