Liam Armstrong (
)
Friends of the Long Island teen killed while crossing train tracks yesterday took to social media today to vent their grief.
Liam Armstrong was celebrating his 18th birthday with pals in Manhattan yesterday when he tried to run across busy subway tracks on the Upper West Side on a dare — and was killed by a train, police sources said.
Armstrong, a popular student at Smithtown HS East on Long Island, had crossed one of four tracks at the 79th Street station when he was hit by a northbound No. 2 express train.
Friends took to Twitter and Facebook to mourn Armstrong, whose private Twitter account bears the tagline “yolo” — short for “You Only Live Once.”
Pal Dylan Nolan tweeted today, “Really is true only the good die young.”
Another friend — briana_lynn1 — tweeted a pic of the popular teen saying “missing you so much already, fly high.”
After the accident, one of the pals who was with him expressed his grief on Twitter.
“Your [sic] my brother, I’m sorry I didn’t protect you,” Dakota Walsh tweeted.
“I can’t believe this happened,” said a tearful friend, Kerin Grisanti, one of many pals who called Armstrong a likable athlete.
“He has three little siblings and he loves them — he’s a great big brother.”
Armstrong and two pals were trying to get to Greenwich Village from Central Park when they mistakenly boarded a northbound No. 1 train.
We they realized their mistake, they got off at 79th Street. Rather than cross to the southbound side above ground, they dared one another to dart across the tracks, police sources said.
At least one friend succeeded in reaching the opposite platform and another was still on the northbound side when the train struck Armstrong just before 6:30 p.m., according to police.
Armstrong suffered a severed leg and died of severe head trauma.
Police sources said a liter of Bacardi rum was in Armstrong’s backpack and two fake IDs were in his wallet.
Friends said Armstrong was set to graduate this year and was considering following his father — a Nassau County detective sergeant — into the police force.
“He was a very nice kid, always making everybody laugh,” said Ali Grimaldi, a senior at Smithtown HS West.
“It was his 18th birthday today, and I think they just wanted to have a little bit of fun,” she added.
A man at the Armstrong family home in Nesconset, LI, declined to comment.
Passengers on the express train that hit the teen said they initially had no idea why it suddenly screeched to a halt — particularly at a local station.
“As we were leaving the train, I actually saw a foot between two cars,” said Jake Moore, 25, of Harlem.
Additional reporting by Yoav Gonen, Kaylee Osowski, Kate Kowsh, Joe Tacopino and Dan MacLeod.