"Mike Cammalleri is a dynamic player who enjoyed great success playing in Calgary," stated Flames general manager Jay Feaster. "We believe Cammalleri will help our offensive production, solidify a second scoring line, bolster our power play, and bring another strong veteran voice to our room. We are confident that a return to Calgary will be good for Mike and good for our continued pursuit of a playoff berth."
Also heading to Calgary are goaltender Karri Ramo and a fifth-round draft pick in 2012.
The Habs received Alberta native and forward Rene Bourque, forward prospect Patrick Holland and a second-round draft pick in 2013.
Cammalleri, who enjoyed a career year in Calgary three seasons ago with 39 goals and 82 points in 81 games, struggled to nine goals and 22 points in 37 games this year. Coming into play on Thursday, Montreal placed last in the Northeast Division with 39 points.
The 29-year-old publicly expressed his frustration with the plight of his former club on Wednesday following a 3-0 home loss against St. Louis the night before, questioning their collective will. He clarified those comments prior to Thursday's contest.
According to several sources, Cammalleri was taken off the bench during the third period of a 2-1 loss to the Bruins in Boston and told to remain at the team hotel to await further instructions. Less than an hour later, the deal was announced.
"There are a lot of young players who have joined our team in the last year who are relatively small. We felt that if we wanted to improve the club, we needed to be bigger up front," said Habs general manager Pierre Gauthier. "We felt since the season started that was one of the things needed to improve."
Bourque, 30, racked up 13 goals and 16 points in 38 games with the struggling Flames, who are 12th in the Western Conference with 45 points heading into a home game against the Anaheim Ducks. He is currently serving a five-game suspension for elbowing Washington Capitals forward Nicklas Backstrom.
Ramo, a 25-year-old native of Finland, has 48 games of NHL experience -- all with Tampa Bay from 2006-09. He posted an 11-21-10 record with a 3.35 goals- against average for the Bolts, but has spent the past three seasons with Avangard Omsk of Russia's Kontinental Hockey League.