High school track star Kristi Bartz, 17, struck and killed by freight train on trestle above popular swim spot

A 17-year-old girl has been struck and killed by a freight train on a trestle above a popular swimming spot during a day out with friends.

Kristi Bartz was on a bridge above the Stillaguamish River in Silvana, Washington around 3.15pm on Saturday when the BNSF Railway train began approaching.

One friend, a male teen, had already jumped into the river below but Kristi and a girlfriend began running when they saw the train, which sounded its whistle and applied the emergency brake.

'We heard the train coming so we were all yelling at them 'there's a train' and they started running,' teen witness Karlie Jensen told KING5. 'We could just hear the footsteps running.'

Tragic: Kristi Bartz, pictured left in her track uniform and right, was struck by a freight train on Saturday afteoon as she planned to jump from a Washington bridge to the water below to swim with friends

The girls were unable to jump because swimmers need to climb to the top of the trestle to be able to leap into the water; they are unable to jump straight from the tracks due to barriers, KING reported.

The other girl was able to get to the side of the bridge and out of the train's path but Kristi was struck as the train traveled at 40mph.

Members of the train crew jumped out to administer CPR on Kristi, but she passed away.

'It's a very tragic situation,' BNSF spokesman Gus Melonas told the Seattle Times. 'This time of year, kids do get on the railroad tracks sometimes.'

Kristi, who lived 30 miles south of the bridge in Snohomish, Washington, leaves behind her parents and two older sisters, Stefani and Michaela. 

Scene: An image shows the bridge (behind) where Kristi was fatally struck in Silvana on Saturday

Danger: The bridge, pictured bottom, is above a popular swimming spot. The train slowed as it saw her and another friend on the bridge but she was struck. The other girl managed to get to the side of the train

The Archbishop Murphy High School senior was a standout student and athlete who planned to attend the University of British Columbia for English and business in the fall.

On Sunday, hundreds of students gathered in the bleachers at the high school to hold a memorial service for the popular teen. 

'She was extraordinary,' her father dad, Manfred Bartz, told the Seattle Times.

'She was just one of those people who was just compassionate, compassionate to anybody and everybody. She was just a humble and loving and very well-loved person.'

Record holder: Bartz, pictured, held two school records in the 800 meter and the high jump

Kristi co-captained the school's team and held two school records in the 800 meter and the high jump. Last week, she broke the school record in the mile run, her father said.

'She really loved life. She loved the outdoors, she loved the water,' her dad said.

She had hoped to travel the world and work with impoverished people, he said.

'Our school is grieving at this time,' Shannon McCann, a spokeswoman for the school, added.