It happened on Monday, March 2 at approximately 5:40 a.m. in Islandia.
A 2005 Toyota was rear-ended by a 2002 Toyota on eastbound Suffolk Avenue, west of Casement Avenue, Suffolk County Police said.
Jennifer Burgess, 36, of East Setauket, who was not involved in the initial crash, stopped to render assistance to the involved motorists, according to police.
A 2014 Toyota and a 2003 Chevrolet then struck the 2005 Toyota, causing Burgess to step into the westbound lane of Suffolk Avenue where she was struck by a 2018 Honda, according to police.
Burgess was transported to Southside Hospital in Bay Shore where she was pronounced dead.
The driver of the Honda, Chris Cardinale, 59, of Saint James, was not injured.
The Honda was impounded for a safety check.
Detectives are asking anyone with information on this crash to call the Third Squad at 631-854-8352.
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