Sandra Bullock movie set stabbing follows bus crash

The Boston, MA, set of crime comedy "The Heat," starring Sandra Bullock and Melissa McCarthy, has been no laughing matter these past few days.

First, 15 people were injured in a bus accident on Monday that involved a collision with a truck associated with the movie. And on Tuesday there was a fatal stabbing near the set in Boston's Roxbury neighborhood.

Boston police say one man was killed and two others were injured after a fight ensued just one block from where "The Heat" was filming. One officer working on the set actually helped chase down a suspect. All of the victims were between the ages of 17 and 21. The survivors injuries are said to not be life threatening.

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Onlooker Cara Lisa Berg Powers recounted the reaction of those working on the film [via The Christian Post]: "The director took the bullhorn and called everyone together... He said three people were stabbed and one of them had died. People were stunned and then the crowd broke up."

Another onlooker, Bradley Fuller, says he saw one of the victims [via Boston Herald]: "...a young guy on the ground and people giving him CPR. They were pumping his chest. It looked like he was only about 14 years old. It's so sad, he's just a baby."

Just a day before the deadly scuffle, a city bus rammed into a parked production truck that was being used for film, causing minor injuries in 15 passengers.

In "The Heat," due in theaters next April, Bullock plays an uptight cop who teams up with an FBI Agent to take down a mob boss.