MOSCOW (AP) — An independent Russian newspaper says a security aide of businessman Yevgeny Prigozhin, who has been indicted in the U.S. for trying to interfere with the 2016 U.S. election, says the Russian mogul has been involved in attacks on several people and at least one killing.

Novaya Gazeta on Monday published an article quoting a former convict who worked for Prigozhin, Valery Amelchenko, who said he orchestrated attacks on Prigozhin's opponents as well as the killing of an opposition blogger at the mogul's behalf.

Amelchenko also said several people working for Prigozhin had traveled to Syria last year to test an unknown poison on Syrians who refused to fight for Syrian President Bashar Assad's government.

Amelchenko disappeared shortly after meeting the Novaya Gazeta reporter and is now on a missing persons list.