"GUN CONTROL NOW. ENOUGH ALREADY," Billy Eichner declared on Twitter after a gunman opened fire at a country music festival in Las Vegas on Sunday night, killing over 50 people and injuring hundreds more.
Since news broke of the horrific incident that took place at the Route 91 Harvest Country Music Festival while Jason Aldean was performing, a number of celebrities have taken to social media to not only offer their condolences to the victims of the attack, but to also speak out about instilling stricter gun control laws in America.
In addition to Eichner, Lady Gaga, Julianne Moore and Emmy Rossum were among the celebrities to post passionate, take-charge messages following the shooting. The hashtag #guncontrol has also started trending on Twitter.
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"Prayers are important but @SpeakerRyan @realDonaldTrump blood is on the hands of those who have power to legislate," Gaga tweeted to America's leaders. "#GunControl act quickly."
Meanwhile, Moore tweeted out a way for her followers to participate in the movement to end gun violence. "I mourn this senseless loss of life. What will it take, #Congress, for you to act? @Everytown @MomsDemand #endgunviolence," the actress wrote. "Today we mourn for Las Vegas, tomorrow we fight for them. Join the movement to end gun violence: Text ACT to 64433."
Here's a look at the other celebrities who are eager to take action in the fight to end gun violence:
Ben Platt: "#guncontrol #guncontrol #guncontrol #guncontrol #guncontrol #guncontrol #guncontrol #guncontrol #guncontrol"
Emmy Rossum: "I believe in prayer, but it's not enough by itself. We need better LAWS. In no world does a CIVILIAN need a MACHINE GUN. Let's fix this."
Hillary Clinton: "Our grief isn't enough. We can and must put politics aside, stand up to the NRA, and work together to try to stop this from happening again."
January Jones: "If you're going to #prayforVegas, you must also #voteforguncontrol, #protestforguncontrol."
Gigi Hadid: "It sickens me the ease in which a TERRORIST can be sold a GUN. Is the ease really worth all these lives ?! This needs to stop."
Harley Pasternak: "As a Canadian, Im confused why automatic rifles and hand guns are legal in US. Who hunts w machine guns/ hand guns? As an American, I'm ashamed."
Ariana Grande: "My heart is breaking for Las Vegas. We need love, unity, peace, gun control and for people to look at this and call this what it is = terrorism."
Joe Biden: "How long do we let gun violence tear families apart? Enough. Congress and the WH should act now to save lives. There's no excuse for inaction."
Leona Lewis: "I'm so devastated by this senseless attack #guncontrol is needed NOW! Too many innocent lives have been taken,it's time to change something."
Ben Stiller: "#LasVegas thinking of all those affected by this horrific gun violence."
Janet Mock: " Give blood, donate ? to orgs, victims, survivors and their families, AND call your reps about gun control."
Billy Eichner: "Congress did nothing after Sandy Hook. NOTHING. Think about how INSANE that is. We're calling Congress about everything else, why not this??"
George Takei: "Will our lawmakers listen this time?"
Elizabeth Banks: "It would be wise to ban assault weapons, high-capacity magazines and silencers. None of which is excessive."
Busy Philipps: "My thoughts and prayers are with all the victims and their families and with everyone who was there. I'm so heartbroken and sickened by what has happened, I honestly don't even know how to process it fully. It's unimaginable and yet, at the same time, horribly unsurprising. But I know we need to work harder to make sure that this stops happening. Because we are failing our children and each other right now. ENOUGH."
Troian Bellisario: "I hate to tell anyone what to do or to make them feel as though I want to take away their rights at a citizen. I do not. But the simple fact is the more guns we have, the easier they are to access, the more tragedies like #lasvegas we will have to endure in our future."
Karla Souza: "Thinking of the lives lost, and those who endured this horrific event in Las Vegas. Thinking of the families and loved ones affected by this tragedy. Let us work towards change: in laws, in how we treat each other. #prayforvegas"
Debra Messing: "We must do more to protect our kids. Bless the souls of the departed, and pray for healing of the injured and the city as a whole. Please join the movement to end gun violence. Text ACT to 64433."
Zendaya: "This is a list of the deadliest mass shootings in recent US history. Now we add the deadliest to this list. There is no post I can make that will heal the pain and heartache that is being felt in Las Vegas today, but we NEED change. We can not continue to let this list grow. We can not grow accustom to waking up to this kind of terrorism in our country. We can not make this normal. How are we going to end gun violence?"
Amy Schumer: "It's not too early to talk about solutions to gun violence; it's too late."
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Schumer has been outspoken about gun control since the summer of 2015 after several people were killed in a mass shooting at a screening of her film, Trainwreck, in a theater in Lafayette, Louisiana.
"I am someone who has a voice right now, and I feel really passionately about it, and it's so heartbreaking," she told ET. "It's just, like, enough. So, if not me, then who? And I hope other people will follow suit."