Provincial police say they responded to a number of fatal incidents over the long weekend while more than 10,000 traffic/marine-related charges were laid.
Ontario Provincial Police said three people were killed in separate road crashes. Two of those killed were motorcyclists.
Two people also died in marine incidents, one involving a motor boat that capsized and the other involving a person who fell off a stand-up paddleboard, police said.
A sixth person died in an off-road vehicle crash.
More than 10,000 traffic/marine-related charges were laid by the OPP between Friday afternoon and Monday night, with 5,847 for speeding and 138 for stunt driving/racing.
Other charges include 458 for not wearing a seatbelt, 192 for impaired driving and 101 for distracted driving.