Train conductor explains what happened moments after he saw three teens tragically die posing for selfies

A train conductor recalled the harrowing moments leading up to a train hitting a group of teenage girls.

In 2011, 15-year-olds Essa Ricker and Kelsea Webster, as well as Kelsea's youngster sister Savannah were out together.

As many teenagers did at the time - and still do - the trio documented their day through pictures to later upload to social media.

But one seemingly harmless selfie tragically cost the girls their lives.

Three teens died in 2011 after being struck by a train (Union Pacific/Essa Ricker/Kelsea Webster/Savannah Webster)

Essa, Kelsea and Savannah took a photo by some train tracks in Utah’s scenic Spanish Fork Canyon and were unaware that a locomotive was coming up behind them.

They unfortunately went on to be hit by the train, dying as a result of their injuries.

John Anderson was the train conductor inside the eastbound Union Pacific train locomotive at the time of the incident.

Also onboard was Engineer Michael Anderson, who blasted the train's horn at the girls to get their attention - but to no avail. They both yelled at the teenagers as well.

"They were in their own little world," recalled John.

Essa Ricker was 15 years old at the time of her death (legacy.com)

"We watched in horror as we got closer. We saw them for about 12 seconds until they disappeared from our sight and the train continued moving forward."

When the was able to ground the train to a halt, John got off to find that Essa and Kelsea were sadly both dead.

Meanwhile, 13-year-old Savannah was badly by the train hurt but still alive.

John said: "I told her everything would be OK and she relaxed a little. I hoped she would make it and for some reason I really thought she would."

Heartbreakingly Savannah didn't make it and her loved ones had to turn off the young girl's life support machine after being told she wouldn't recover from the brain injuries she was left with.

Just moments for her death, Savannah posted to her Facebook page: "Standing right by a train ahaha this is awsome!!!! [sic]"

Giving an update at the time, Savannah and Kelsea's mother, Jayna Webster, penned on a blog, as per MailOnline: "We spoke to the doctors today and they informed us that Savvy's brain injuries were too great.

Even though they've had done everything possible Savannah will not be able to recover any further. We will keep her on life support till the end of the day, but its time to say good bye, for now, to an angel that walked among us."

Savannah died on October 18, 2011, a few days after her sister and Essa.

If you have experienced a bereavement and would like to speak with someone in confidence, contact The Compassionate Friends on (877) 969-0010.