GLENDALE, AZ — Valley community members climbed stairs at Desert Diamond Arena in Glendale on Saturday to remember first responders killed in the terrorist attacks on September 11, 2001.
Thursday marks 24 years since that day, which was the deadliest terrorist attack in history.
More than 1,000 people, including firefighters and other first responders in full gear, participated in the 9/11 Tower Challenge. They climbed 2,071 arena stairs, which was the number of steps it took to climb the World Trade Center's twin towers.
Mesa police officer Kylie Thesz is participating for a second year.

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“I can very distinctly remember looking at the TV when the second tower was hit,” Thesz said. “My mom was a flight attendant at the time.”
Everyone in the challenge wore a lanyard with the picture of one of the first responders who died that day.
“This is Father Mychal Judge, and he was the first fatality on 9/11,” Jason Schechterle said as he showed the picture around his neck. “These other firefighters carried him, laid him at the altar, and then they went back inside the building, and they never came out.”
Schechterle is a former Phoenix police officer who was badly burned after another driver hit his patrol car. He now works for the 100 Club of Arizona.
Proceeds from the 9/11 tower challenge benefit the 100 Club, which provides first responders and their families with financial assistance after line-of-duty deaths or injuries.