FILE PHOTO: U.S. Secretary of State John Kerry (L) speaks with Hossein Fereydoun (C), the brother of Iranian President Hassan Rouhani, and Iranian Foreign Minister Javad Zarif (R), before the Secretary and Foreign Minister addressed an international press corps gathered at the Austria Center in Vienna, Austria, July 14, 2015. REUTERS/US State Department/Handout via Reuters

BEIRUT (Reuters) - The brother and close advisor of Iranian President Hassan Rouhani was transferred to hospital on his second day of detention, according to reports on Iranian news sites.

Hossein Fereydoun was summoned for questioning on Saturday in a corruption case in which he faces unspecified charges. He was later detained when he could not post bail, which was set at more than 15 million dollars, according to Fars News.

The Mehr news site later reported a representative had posted bail on Fereydoun’s behalf on Monday evening so he would not need to return to prison from hospital. The site did not specify the amount of the bail posted.

Fereydoun is a senior diplomat who took part in the talks that led to a 2015 nuclear agreement between Iran and world powers. Some Rouhani supporters have interpreted the charges against him as a move by the hard-line judiciary to discredit the president.

Fereydoun appeared in court on Monday but was transferred to hospital after appearing unwell, according to the Tasnim news site.

“Fereydoun’s health was not good from the moment he appeared in court and, ultimately, because his health situation became critical, the questioning session did not take place and the accused left the court in an ambulance,” Tasnim reported.

No further information was provided about Fereydoun’s health. Rouhani has not made any official statement about his brother’s detention or hospitalization.