Rising hockey star Alexei Cherepanov died of a heart attack Monday night after collapsing during a game in the Moscow region city of Chekhov.

The 19-year-old, who was the first round pick of the New York Rangers in this year's National Hockey League draft, was playing for Avangard Omsk in the Continental Hockey League.

He lost consciousness on the bench late in the third period of Monday's game, and attempts to revive him were unsuccessful. He was pronounced dead a the hospital later that night.

A statement posted on the Continental Hockey League's web site on Tuesday afternoon listed the official cause of death as "acute heart failure."

The statement said there had been no ambulance at the arena. League regulations require the home team to provide emergency medical personnel and an ambulance at all games.

Sports, Tourism and Youth Policy Minister Vitaly Mutko promised "serious changes in the provision of medical aid in Russian sport" as a result of Cherepanov's death, Interfax reported.

"A person should not be allowed to compete if he has ischemic heart disease," Mutko said. "This shows that initial evaluations and monitoring of a player's health is missing."

Cherepanov's agent, Jay Grossman, said he was unaware of "any sort of existing condition," the Canadian Press reported.

Vladimir Semyonov, the Moscow region health minister, said an ambulance had arrived quickly and was fully equipped.

Reports in the Russian media, however, said the ambulance had taken 15 minutes to arrive and that the defibrillator with which it was equipped was not working.

The Investigative Committee of the Moscow Regional Prosecutor's Office has opened an investigation into Cherepanov's death, spokeswoman Yulia Zhukova said Tuesday.

"I think the signs of negligence are evident," Pavel Krasheninnikov, head of the governing board of the Russian Hockey Federation, said in relation to the initial lack of an ambulance, Interfax reported.

The press secretary for Vityaz, Avangard's opponent in Chekhov, could not be reached for comment Tuesday afternoon. The assistant director at the arena hung up Tuesday when contacted for comment.

The medics who had tried to revive Cherepanov were assaulted after the incident, Interfax reported, citing a police source. A police spokeswoman in Chekhov said no such attack had been reported.

Cherepanov had reportedly planned to play for New York after one more season playing in Russia.