Congresspeople and activists are calling to stop a bill that will loosen restrictions on guns in the aftermath of the deadliest shooting in modern U.S. history.Sunday night, gunman Stephen Paddock opened fire on crowds attending a music festival in Las Vegas, killing 58 people and injuring more than 500 before allegedly turning the gun on himself. He was found shot in his hotel room, officials said.

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Monday afternoon, U.S. President Donald Trump condemned the attack as an “act of pure evil.”Later Monday, House Democratic leader Nancy Pelosi asked Speaker Paul Ryan to create a select committee on gun violence, saying that while today was a day of mourning, it should also be used to take action to combat gun violence.WATCH: President Trump holds moment of silence at WH for Las Vegas shooting victims 
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President Trump holds moment of silence at WH for Las Vegas shooting victims – Oct 2, 2017
“Today, our nation woke up to news of the worst mass shooting in our history,” she wrote in a letter.
“Congress has a moral duty to address this horrific and heartbreaking epidemic.”
She also asked Congress to pass the King-Thompson legislation which she says strengthens background checks.Before the shooting that killed at least 58 people, House GOP leaders had been moving forward with legislation to ease regulations on gun silencers and allow those with concealed-carry permits to take their weapons to other states.WATCH: Trump will not re-open gun control debate following Las Vegas shooting 
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Trump will not re-open gun control debate following Las Vegas shooting – Oct 2, 2017
Rep. Jeff Duncan of South Carolina sponsored the silencer bill, saying it would help hunters protect their hearing.Democrats scoffed, noting that the bill also would allow more armor-piercing ammunition. Pelosi invoked the shooting of Majority Whip Steve Scalise to oppose the bill last week, saying “if you can hear (a gunshot) you can run” away.

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The husband of Gabby Giffords, the Arizona Congresswoman who survived a shooting in 2011, spoke in the Capitol against the legislation Monday afternoon. Mark Kelly also urged for action to combat gun violence.“Your thoughts and prayers aren’t going to stop the next shooting. Only action and leadership will do that,” he said at a press conference.
“Imagine how much worse last night’s shooting could have been if the gunman had a silencer.”
“We don’t have to accept this as normal. It’s not normal. It’s not inevitable. It’s an epidemic that needs to be cured.”WATCH: Gabrielle Giffords, Mark Kelly renew call for gun control laws in wake of Las Vegas shooting
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Gabrielle Giffords, Mark Kelly renew call for gun control laws in wake of Las Vegas shooting – Oct 2, 2017
When asked at the White House press briefing on Monday, press secretary Sarah Huckabee Sanders said it was too early to start a political debate about gun control.“This is an unspeakable tragedy, today is a day consoling the survivors and mourning those we lost… there is a time and place for political debate but now is the time to unite as a country,” she said.“A motive is yet to be determined, and it would be premature for us to discuss policy before we know all the facts.”— with files from the Associated Press