According to police, a man was running across Middle County Road near Adirondack Drive in Selden around 6:35 p.m. when he was struck by an SUV.
He was knocked into the middle of the roadway and then struck again by another vehicle.
Meanwhile, Suffolk County Police say a car struck a pedestrian on the William Floyd Parkway near Roberts Road in Shirley around 6:50 p.m.
The 70-year-old driver remained at the scene.
Both victims were pronounced dead at the respective scenes and police are investigating.
Earlier in the day, Acting Suffolk County Police Commissioner Stuart Cameron announced the addition of seven officers to the Suffolk Intensified Traffic Enforcement (SITE) Team.
That doubled the size of the group that will be focused on enforcement on major roadways.
"Motorists should expect to see large, this large number of police officers doing traffic enforcement on our major roadways," said Suffolk Police Chief Stuart Cameron.
Before Fridays incidents, Eyewitness News had found that since October 1, 11 pedestrians had been struck and killed on Long Island, the majority of them in Suffolk.
Robert Sinclair, with AAA, said November is considered the deadliest time of year for pedestrians because of Daylight Saving Time. In New York City, the number of accidents involving pedestrians typically doubles from two per day to four per day.
Cameron urged drivers to slow down during this daylight transition period.
"People that normally commute home from work during the daylight suddenly are plunged into doing it in darkness," he said. "It does take an adjustment period so we do see an uptick in accidents."
Cameron said the department is also launching a pilot program using a traffic data dashboard to pinpoint where traffic enforcement should be emphasized moving forward.
Suffolk Police Officer Timothy Thrane remains in a medically induced coma at Stony Brook University Hospital after being involved in a collision caused by an alleged drunk driver, also on the William Floyd Parkway in Shirley.
Thrane - a father of three - was standing outside his patrol vehicle in Yaphank early Wednesday morning directing traffic at an accident site when police said William Petersohn crashed into a car, which crashed into another car, striking Thrane. He suffered a serious brain injury.
Eyewitness News spoke with Thrane's colleague Officer CJ Hutter outside the hospital.
"We all think it's disgraceful that the person that caused this all to happen has been released from law enforcement custody under cashless bail," he said. "Meanwhile, our police officer is still up there fighting for his life."
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