Young ice hockey star Aleksey Cherepanov, who died of a heart attack during a game in October, had been taking performance enhancing drugs, the Investigation Committee of the Prosecutor General's Office says.

The 19-year-old collapsed during a Continental Hockey League (KHL) game in the Moscow region.

The official statement of the investigation committee says:

“No traces of alcohol or drugs were found in his blood and urine, however, tests for chemicals showed that Aleksey Cherepanov had been using stimulants for several months.”

It was also discovered that Cherepanov, nicknamed the Siberian Express, was suffering from chronic myocarditis, which meant he should not have been playing sport. According to a post-mortem examination, the sportsman developed the disease approximately a year before his death.

Aleksey Cherepanov

The investigation also found that: “the paramedics called in for Cherepanov committed a number of gross violations”.

The report says they “arrived 12 minutes after the call and did not have a properly charged defibrillator. In addition, the brigade's chief doctor wrongly diagnosed a ‘natural death’.”

The Omsk Avangard forward was one of the most promising hockey stars in Russia. A first-round draft pick of the New York Rangers, Cherepanov was expected to move to National Hockey League.

The Prosecutor General’s Office says they will continue their investigation and warned that the doctors involved in Cherepanov's treatment may face legal action.