Karpovtsev, 41, was serving as an assistant coach for Lokomotiv Yaroslavl. He played 12 seasons in the NHL with the Rangers, Toronto, Chicago, the Islanders and Florida.
"We stand together with the entire KHL, NHL and hockey world in mourning today's tragic news concerning the Lokomotiv Yaroslavl hockey team," the Hawks said in a statement. "The tragedy affects the Chicago Blackhawks family directly as we mourn the losses of Alexander Karpovtsev and Igor Korolev, two players who spent time with our organization and that our fans know well. Our thoughts and prayers are with the families and friends of the Lokomotiv Yaroslavl organization."
Karpovtsev and three Rangers teammates were the first Russian players to have their names engraved on the Stanley Cup. He had three goals and 15 assists with a plus-minus of 12 that season.
Korolev, also 41, was a Hawk from 2001-04. In 12 NHL seasons with St. Louis, the Winnipeg-Phoenix franchise, Toronto and Chicago, he scored 119 goals in 795 games.
"I don't think anybody can prepare for something like this," Lamoriello said. "It's just devastating news. Words can't express my personal feelings."
Vasyunov left the Devils in the offseason to sign with Lokomotiv.
The KHL team was flying to Minsk, the capital of Belarus, to take on Dinamo Minsk on Thursdsay night in their season opener. But the plane crashed into a river bank while taking off in western Russia, killing at least 43 and leaving two others injured, officials told The Associated Press.
"I can't say enough about him as a young man," Lamoriello said of Vasyunov. "He certainly had talent. His whole career was in front of him."
Vasyunov compiled one goal and four assists for the Devils last season. A left winger, he was selected by the team in the second round (No. 58 overall) of the 2006 NHL draft.
Rachunek, a defenseman, appeared in 47 games with New Jersey in 2007-08, compiling four goals and nine assists. He also played with the Rangers in parts of the 2003-04 and 2006-07 seasons, compiling seven goals and 23 assists in 78 games.
The 32-year-old native of Zlinwaldow, Czech Republic, appeared in 371 career NHL games, compiling 22 goals and 118 assists. He was selected by the Ottawa Senators in the ninth round (229th overall) of the 1997 NHL draft. He played parts of five season in Ottawa.
Vasicek, a center, appeared in 81 games for the Islanders in 2007-08, getting 16 goals and 19 assists.
The 30-year-old native of Havlickuv Brod, Czech Republic, appeared in 460 career NHL games, compiling 77 goals and 106 assists. He was selected by the Carolina Hurricanes in the fourth round (91st overall) of the 1998 draft. He played with the Hurricanes for six seasons.
"On behalf of the entire Devils organization, our thoughts and prayers go out to the families and loved ones of the entire Lokomotiv club," Lamoriello said in a statement issued by the Devils.