Story highlights Sofya Tsygankova is accused of killing 5-year-old Nika Kholodenko and 1-year-old Michela Kholodenko

She suffered multiple stab wounds that authorities believe were self-inflicted

Tsygankova is the estranged wife of world-renowned pianist Vadym Kholodenko

(CNN) The estranged wife of world-renowned pianist Vadym Kholodenko was arrested Monday in Texas in the stabbing deaths of their two daughters.

Sofya Tsygankova is accused of killing 5-year-old Nika Kholodenko and 1-year-old Michela Kholodenko. Tsygankova also suffered multiple stab wounds, but authorities believe those were self-inflicted, said David Babcock with Benbrook, Texas, police. Benbrook is near Fort Worth.

"She's still undergoing the mental evaluation, but she's now being also being held on our charges as well," he said.

Kholodenko found the children when he went to pick up his daughters from his estranged wife's home on Thursday. He called 911.

"Being in a great grief, I would like to address this message to everyone who thinks about my family. The loss of my children will be with me forever. But I would like to say that I feel the support of the Fort Worth community and all people who are sending me messages all over the world," he said last week.

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