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Friends Mourn Long Island Teen Killed Crossing Train Tracks on Birthday

By  Trevor Kapp Ben Fractenberg Murray Weiss and Carla Zanoni | March 27, 2013 6:35pm | Updated on March 29, 2013 10:35am

NEW YORK — Schoolmates of a popular Long Island teen killed by an uptown 2 train as he celebrated his 18th birthday in Manhattan searched for meaning behind the tragedy and consoled each other through social media Wednesday.

Liam Armstrong, a Smithtown High School East senior who followed his buddy across the tracks carrying a bottle of Bacardi in his backpack, was mowed down by the express train at the 79th Street station about 6:30 p.m. Tuesday, the day before his birthday. 

Armstrong, the son of a Nassau County police detective, cut loose in the city about 2:30 p.m. on Tuesday with lacrosse teammates Dakota Walsh and Ryan Van Duyne, hanging out in Central Park for a few hours before heading to the subway on their way down to Greenwich Village, police sources said.

But the party hit a snag when the crew accidentally boarded an uptown train instead. After realizing their mistake, they got off at the 79th Street stop and misguidedly decided to take a fatal shortcut across the tracks, sources said.

One of the boys made it across, but Armstrong couldn't outrun the speeding train. The third boy stayed on the uptown platform.

Armstrong died from multiple blunt force trauma injuries to his head, neck, and torso, the Medical Examiner's office said Friday.

"You're my brother. I'm sorry I didn't protect you," a guilt-ridden Walsh tweeted Wednesday.

Classmates were quick to reassure the despondent teen that the death was not his fault.

"its not your fault man dont put this burden on you you did all that you could you were a great friend to him thats amazing," tweeted shauuuuuunnnnn, ‪@sptsoccer3.

Others simply mourned the ace 150-pound midfielder for the Smithtown High School East Bulls.

"I miss you so much already @Liam6567371 best friends forever❤❤" posted friend Alisah Zeni.

Friends set up three Twitter feeds using the hashtags #liamarmstrong, #ripliam and #staystrongsmithtown to channel their grief.

The fallen teen's family — father, Christopher Armstong, a 22-year veteran with the Nassau County Police department, mother Barbara Brennan-Armstrong and three siblings — grieved in their Nesconset home, declining to speak to the press.

The varsity lacrosse team's scheduled game against Port Washington High School was canceled Wednesday as students tried to make sense of the death.

"He was a vibrant young man who will be missed by all who knew  him. Our heartfelt thoughts and prayers go out to his family," school superintendent Anthony J. Annunziato said.

The school's flag flew at half-staff on Wednesday.

Employees at the Middle County Road Wendy's where Armstrong worked for two years said they were also grieving the loss.

''He was a good worker," said the restaurant's manager, who declined to give her name. "He was well liked. He'll be missed."