HOBOKEN, N.J. -- Family members say the cousin of Ben Simmons, who was picked first by the Philadelphia 76ers in the NBA draft, has died after being struck by a car in a New Jersey neighborhood.

Twenty-one-year-old Zachary Simmons died after being struck early Saturday while crossing a street in Hoboken. Authorities say the sport utility vehicle that struck the Ramsey man fled the scene.

The victim's mother, Monique Steele, told WCBS-TV her son had gone with Simmons to the NBA draft earlier in the week. She said he was walking back from a friend's birthday party when he was struck and killed.

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Ben Simmons posted a photo Saturday night on Twitter showing him standing with his cousin. The caption read: ''#ripZacharySimmons.''

Hearing the news this morning is a reminder to never forget the important things in life.

— Ben Simmons (@BenSimmons25) June 26, 2016

#ripZacharySimmons 🙏🏽 pic.twitter.com/3MXEOn0xTW

— Ben Simmons (@BenSimmons25) June 26, 2016

I'm glad I could share this moment in my life with you. Rest in peace Cuzzo . Much love Zachary Simmons #rip🙏

— Ben Simmons (@BenSimmons25) June 26, 2016

Police were still searching for the fleeing vehicle Saturday night.