On Valentine's Day, Jared Block, a sophomore at Marjory Stoneman Douglas High School, who was born and raised in Cherry Hill, heard gunshots, then took cover in a large storage closet with his other drama-class schoolmates until a SWAT team freed them 90 minutes later, urging them to run out of the building.

The 16-year-old survived that deadly day when a former classmate fatally shot 17 students and faculty members at the school in Parkland, Fla. – and unleashed an extraordinary movement by young people for changes to gun laws.

"Be the voice for those who don't have one," Jared said during a CNN town hall meeting in Florida after the shooting.

On Sunday, he brought his call-to-action to Lower Merion Township via Skype.

"If it can happen in Parkland, it can happen anywhere," Jared, at home in Parkland, said to about 90 Hebrew school students and their parents at the Har Zion Temple in Penn Valley. The students are part of the Lower Merion Area Hebrew High program for teens.

Jared was joined by his parents, Gayle and Josh. Together, they urged action regardless of political persuasion. Marches. Calls to elected officials. Continued speaking about Parkland until someone finally does something, they said.

"Please be the voices behind all these kids in Parkland," said Gayle Block, a Huntingdon Valley native and former Philadelphia School District teacher at Harding Middle School in Frankford for six years.

The Blocks moved to Florida in 2012, where they were living in a "bubble" in the small, tight-knit community of Parkland before the shooting at Marjory Stoneman, she said.

"We are now part of that bubble that burst," Gayle Block said.

Days later, sadness turned to anger "at what this monster has done not only to Parkland but to my little family of four — my kids who were scared to walk into a dark room … I had to lay with them in bed until they fell asleep," she said.

The shooting suspect, Nikolas Cruz, 19, has been jailed on 17 counts of murder and has admitted the attack, authorities said. Warnings to authorities that he was a danger capable of shooting up a school went unheeded.

"Hug your kids," Josh Block told the gathering at Har Zion, where his sister, Kami Verne, is a congregant.

Norman Einhorn, director of the Lower Merion Hebrew school program and of member engagement at Har Zion, organized the hour-long event to emphasize the importance of taking action and speaking out. In an earlier interview, he noted that the post-shooting hashtag, #neveragain, was the rallying cry among Jews following the Holocaust.

Also joining the Skype conversation were U.S. Rep. Ted Deutch, a Florida Democrat who represents Parkland and who has been outspoken about a ban on assault-style weapons, and John Wood Jr., director of media development for the nonpartisan group Better Angels, which seeks to unify people from different parts of the political spectrum.

From a large projection screen at Har Zion, Jared described practicing a song for the spring musical, "Yo Vikings," in his drama class on Feb. 14 when he heard a fire alarm. As he and his classmates started heading toward the door, Jared said he heard "hollow" and "ricocheting" sounds "like a trash can was falling over," which he later realized were gunshots from the next building over.

"My teacher was screaming at us, like, 'Go in the closet. Go. Go. Go!" he recalled. About 60 to 70 in all would huddle in that closet, getting only snippets of information on cell phones.

Jared was able to text his mother. His parents rushed to the school, but were kept outside for hours before they could be reunited.

"What keeps me motivated is that I'm still alive," he told Tes Goldman, 16, when the Lower Merion High School sophomore asked how he stays strong. "I'm going to be the voice for the 17 people … They're looking down now on us, telling me, 'You need to fight for this so I'm the last person.'"

After the Skype session, Sydney Schur, 15, a sophomore at Lower Merion High School, said she will tell classmates in morning announcements:

"We need to take advantage of this opportunity to make a change and make our voices heard."