Late in the third period last night during the game between the Panthers and the Capitals, the refs blew the whistle so they could drop the puck again, and after the whistle was blown, the Panthers slashed Alex Ovechkin.
While these types of slashes are relatively common in the NHL, they are still dangerous and have the capability of breaking a players hand. Additionally, the fact that this came after the whistle was blown makes this play even more cheap and hints at an intent to injure.