A court in Kyiv heard motions on March 6 in the corruption case against Roman Nasirov, Ukraine's tax and customs service chief.
Nasirov was suspended from his post on March 3 amid a graft investigation that marks a rare attempt to prosecute a senior official on suspicion of corruption.
A special prosecutor tasked with fighting corruption has sought Nasirov's arrest on suspicion of "abuse of office leading to serious financial losses," citing concerns that he could try to flee the country.
Nasirov's suspension came a day after the National Anticorruption Bureau (NABU) said it attempted to serve the 38-year-old, who was in a Kyiv hospital at the time, with a document identifying him as a suspect in the case of fraud and embezzlement of the equivalent of more than $100 million in tax revenues from natural-gas delivery contracts.
Soon afterward, Nasirov was transferred to an intensive care unit after suffering what a doctor said was a heart attack.
With reporting by RFE/RL's Ukrainian Service and AP