Melanie Eversley

USA TODAY

A prominent Russian millionaire and former official under Vladimir Putin found dead last year in a Washington hotel died of blunt force injuries to the head, Washington's Office of the Chief Medical Examiner announced Thursday.

Beverly Seals, chief of staff, confirmed the finding involving the death of Mikhail Lesin, former head of media affairs for the Russian government. Initial reports placed Lesin's cause of death as a heart attack. He was found dead Nov. 5 at the Hotel Dupont, where he'd been staying.

In a joint statement released Thursday, the Office of the Chief Medical Examiner and Washington's Metropolitan Police Department identified the cause of death for Lesin, 59, as "blunt force injuries to the head." The statement also identified "other contributing factors" as "blunt force injuries of the neck, torso, upper extremities and lower extremities."

The statement said the manner of death was undertermined.

Russian Foreign Ministry spokesperson Maria Zakharova said on Facebook that the Russian embassy "repeatedly" sent inquiries about the investigation into Lesin's death.

"The American side did not provide us with any substantial information," she wrote. "We await from Washington an explanation and official information about the investigation. If the information reported in the media today is confirmed, Russian authorities will send the American side a request for international legal assistance."

Putin's spokesman Dmitry Peskov said: "One can’t say that [the reasons for the Lesin’s death] were reported now — this is just a collection of information, which is largely impersonal, published in the media,” the TASS news agency reported Friday.

“We have not received any detailed information over the channels established for this kind of information and we expect to receive this detailed information,” he added.

At the time of his death, it was unclear why Lesin would have been in the United States.

He served as Russia's minister of press from 2009 to 2014, according to ABC News, often traveling with Putin on official trips.

Anna Arutunyan contributed to this report.