(CNN) Marjory Stoneman Douglas senior Ryan Deitsch asked Florida Sen. Marco Rubio on Wednesday why he and other students "have to march on Washington just to save innocent lives."

Deitsch, who survived the shooting that left 17 people dead last week at his Parkland, Florida, high school, told Rubio he has grown up in a world with drills in schools and possible active shooters. In fifth grade, he hid in a bathroom with his teacher and 20 classmates for three hours after a shooter came to his town, Deitsch recalled.

"Now seven years later, I'm in a closet with 19 other kids, waiting, fearing for my own life," he told the Republican lawmaker at the CNN town hall "Stand Up: The Students of Stoneman Douglas Demand Action" in Sunrise, Florida.

Deitsch asked Rubio why do students have to be the ones demanding action on gun control laws. "Why do we have to march on Washington just to save innocent lives?," he said.

Rubio told the student: "You're right."

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