About 300 mostly young people filed Friday evening into St. Gregory the Great Catholic Church in Amherst — many with heads bowed and solemn expressions that belie carefree youth.

They, along with about 60 adults, were there to remember four teenagers killed Sunday in the horrific crash at County and Strickler roads in Clarence and to embrace their grief by embracing each other.

“Young people know what to do in a tragedy. They gather immediately,” said the Rev. Paul Salemi, of St. Gregory’s.

“Adults seem to lose that. We all get all [wrapped up] without realizing what needs to be done . . . without realizing what’s important. And all of you realized what was important at that moment. Not to run. Not to show anger, but to let down those walls and simply be with each other,” Salemi said.

Hours after the accident Sunday, friends of the victims erected a memorial at the crash site. During the service, a choir made up of all young people sang songs of faith and hope, and friends of the four victims were invited to share their thoughts and present readings.

About the shrine, Salemi said, “I was moved to see how fast flowers and teddy bears, cigarette packs and lighters and a cross [appeared] and how fast all of you were moved to remember your friends.”

Friday, in the church’s Perpetual Adoration Chapel on Maple Road, the young people hugged and a few wept openly. Hillary Blanchard, a friend of Megan Schnorr, one of the victims, was invited to share one of Megan’s poems.

In addition to Schnorr, 16, of Amherst, the other victims of the accident were Viktor Shapiro, 18, of Amherst, the driver of the vehicle; and passengers Mark Brown, 19, of Getzville, and Amanda Slisz, 16, of Amherst.

Also remembered at Friday’s prayer service were Jacob Herbert of Clarence, who was fatally stabbed early last Saturday outside a Lisbon Avenue house in Buffalo, and Chelsea Oliver of Snyder, an Amherst High School student who died of an illness last weekend.

Joseph Chernowski, director of youth ministry at St. Gregory the Great, read several messages that were posted to victims online.

“Over the past two days, I’ve been watching what you guys have been writing online, what you have written to your friends, about your friends, and I have been amazed [at] the unashamed outpouring of love, of emotion, of grief and of loss,” Chernowski said.