Richard M. Mackey, 29, died early Monday, May 20, from his injuries, said Ramapo Police.
His brother Raymond Mackey, also 29, from Sloatsburg, is believed to be the driver of the lawn mower and is currently hospitalized with serious injuries at this time, police added.
According to police, the Sloatsburg brothers were driving the riding lawn mower when the attempted to cross Route 17 and inadvertently drove into traffic and were struck by a 2006 Honda that was traveling southbound, police said.
The operator of the Honda, a 49-year-old Monroe man, remained on scene and cooperated with police.
The two brothers were treated by Rockland Paramedics and Sloatsburg EMTs and transported to Hackensack Medical Center.
The Ramapo police Crash Investigation Unit, along with the Ramapo Detective Bureau is currently investigating.
There have been no summonses or charges at this time.
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