Singer Lady Gaga was among the celebrities calling for more gun control following the largest mass shooting in U.S. history in Las Vegas Sunday night. The Grammy-award winning singer tweeted at House Speaker Paul Ryan and President Trump that “blood is on the hands of those who have power to legislate,” in response to Ryan’s call for prayers.

“Prayers are important but @SpeakerRyan@realDonaldTrump blood is on the hands of those who have power to legislate. #GunControl act quickly,” she said.

Prayers are important but @SpeakerRyan @realDonaldTrump blood is on the hands of those who have power to legislate. #GunControl act quickly. https://t.co/bXZQ7enuEp — xoxo, Gaga (@ladygaga) October 2, 2017

In an earlier tweet, she called for Democrats and Republicans to unite and enact more gun control.

This is terrorism plain and simple. Terror bares no race, gender or religion. Democrats & Republicans please unite now #guncontrol ???? — xoxo, Gaga (@ladygaga) October 2, 2017

Lady Gaga announced later that she was holding a “20 minute moment of meditation/silence/prayer on my InstagramLive” for "calming of the world."

4 anyone who'd like to join, I'm doing a 20 minute moment of meditation/silence/prayer on my InstagramLive for calming of the ?? @ 3:30 PST — xoxo, Gaga (@ladygaga) October 2, 2017

Actress Julianne Moore also called for more gun control and blamed Congressional inaction on gun control tweeting, “I mourn this senseless loss of life. What will it take, #Congress, for you to act?”

Other singers and performers simply relayed their prayers for the victims’ families.

There are no words to express the helplessness and sorrow my broken heart feels for the victims in Vegas and their families. — Taylor Swift (@taylorswift13) October 2, 2017

Saying a prayer for all the victims & their loved ones, also for the residents & visitors of Las Vegas! This was a horrific act of terror!! — Rihanna (@rihanna) October 2, 2017

The Sunday night shooting at the Route 91 Harvest festival left over 50 dead and over 500 injured. Many prominent Democrats, including Hillary Clinton and Sen. Richard Blumenthal, immediately called for increased gun control in light of the shooting.

Police are continuing to investigate a motive and how the shooter, Stephen Paddock, 64, obtained the weapons used in the shooting.