Yulia Tymoshenko is serving a 7-year prison sentence after being convicted on charges she abused her authority when brokering a natural gas deal with Russia's Gazprom in 2009, when she was prime minister.
She declared a hunger strike April 20 in protest of her treatment in prison.
Eugenia Tymoshenko, her daughter, said her family was worried about Yulia Tymoshenko's health. The former prime minister has bruises on her body that she claims came from prison authorities.
"I appeal to every Ukrainian -- don't be indifferent," she was quoted by the former prime minister's Web site as saying. "If (President Viktor) Yanukovych's regime did this to the former prime minister, think about what they can do to you."
Yanukovych had said he called on the general prosecutor's office to investigate Tymoshenko's claims of abuse. Her supporters have expressed concern and said they believe the charges against her are politically motivated.
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