Pittsburgh Shooting - Oct. 27, 2018

Police rapid response team members respond to the site of a mass shooting at the Tree of Life Synagogue in the Squirrel Hill neighborhood on October 27, 2018 in Pittsburgh, Pennsylvania. According to reports, at least 12 people were shot, 4 dead and three police officers hurt during the incident. The shooter surrendered to authorities and was taken into custody. (Photo by Jeff Swensen/Getty Images)

Stars are speaking out following a deadly mass shooting at a Pittsburgh synagogue.

According to the Associated Press, a gunman opened fire during a baby-naming ceremony at the Tree of Life Congregation in the city’s Squirrel Hill neighborhood on Saturday morning, killing at least 10 people. The outlet reports that six people were injured, as well as six police officers.

In the wake of the tragedy, dozens of politically outspoken celebrities took to Twitter to mourn the massive loss and call their followers to action.

“My heart is broken for Pittsburgh and for the grieving Jewish community there,” Josh Groban tweeted. “Words matter. Hate speech, dog whistling at our highest levels…it results in real consequences. This is a great tragedy. *another* great tragedy.”

Lauren Jauregui also raised her voice, calling attention to the alarming frequency of racially motivated mass shootings in the United States.

“White bigots are continuing to murder minorities in the United States and being civilly arrested,” she tweeted. “I will never shut up about what’s going on until everyone starts to truly realize what kind of time we’re living in again and DOES something about it.

Niall Horan, meanwhile,

President Trump’s reaction
to the shooting and called for better gun control.

“Trump kept saying in his chat with reporters that if there was an armed guard inside the synagogue that the ‘numbers’ would have been a lot lower,” the “Slow Hands” singer wrote. “The fact is if there was no guns at all, there wouldn’t have been a shooter in the first place. Get a grip.”

For her part, Mandy Moore encouraged followers to funnel their frustration with the current climate of violence into their votes on Election Day.

“My heart goes out to all those affected by gun violence today and every day,” the “This Is Us” actress tweeted. “Feeling helpless and frustrated by this news too? VOTE Nov 6th. VOTE. Use your voice.

Ellen DeGeneres also took to Twitter, sending a heartwarming message of peace and unity to all.

“Today, I send out love to each and every one of you reading this. Every single one of you,” she wrote. “We are one world. We all need love. We all want comfort. Let’s give it to each other.”

See more reactions from stars below.