A former senior cleric in the Russian Orthodox Church said on Monday that Czech police had found small containers of a white substance in his car during a search a day earlier, and denied any connection to those items.

Metropolitan Hilarion, whose secular name is Grigory Alfeyev and who headed the church's external relations from 2009 to 2022, accused police of not following correct procedure during the search in the Czech Republic and called for an independent investigation.

He also "categorically denies any involvement in the illegal possession of prohibited substances and considers what happened to be a provocation," a post on his Telegram page said.

Police did not inform Hilarion why his vehicle had been stopped and did not allow him to witness the search, the Telegram post said. 

The statement said the incident was preceded by a long period of pressure on Hilarion and the Orthodox community he serves in the Czech town of Karlovy Vary, including anonymous and sometimes violent threats.

Moscow is demanding Hilarion's immediate release and the termination of the "fabricated" proceedings against him, Russian Foreign Ministry spokeswoman Maria Zakharova said in a statement.

"The head of the Czech diplomatic mission in Moscow will shortly be summoned to the Russian Foreign Ministry, where a strong protest will be lodged regarding the unacceptable high-handedness of the Czech authorities," she said.

A spokesperson for the Czech police's National Drug Headquarters, responding to a request for comment, said the agency conducted a search after receiving an anonymous tip. 

She did not comment directly on whether a substance had been found, on the identities of those involved or provide further details, citing ongoing criminal proceedings.