A survivor of the school shooting in Parkland, Florida has said policymakers “need to look in the mirror and take some action”.

“My sister is a freshman, and she had two of her best friends die - that’s not acceptable. That is something we should not let happen in this country,” said senior David Hogg during an appearance on CNN. “We need to dig out of this hole… there is something seriously wrong here. And some of our policymakers... need to look in the mirror and take some action because... without action, ideas stay ideas and children die.”

At least 17 students at Marjory Stoneman Douglas High School, about 45 miles north of Miami, were killed after a gunman opened fire on them with an automatic rifle. It was one of the deadliest school shootings on record in the US. Officials said another 14 were seriously injured.

The suspect has been identified as 19-year-old former student Nikolas Cruz, who was arrested after a brief manhunt. Mr Cruz had been expelled for “disciplinary reasons”, while teachers said they had previously been warned that he could pose a danger to the campus.

The incident has again demonstrated the divide between Democrats and Republicans on gun policy.

“Please don’t pray for me. Your prayers do nothing. Show me you care in the polls,” wrote another survivor on Facebook. In a long post, junior Cameron Kasky blasted Florida's Republican senator Marco Rubio and Republican Governor Rick Scott.

At Capitol Hill in Washington, Republicans offered their condolences while Democrats called for action.

Senate Democratic Leader Chuck Schumer on the Senate floor said it was time to do something about the gun violence epidemic.

Florida shooting – in pictures Show all 10 1 /10 Florida shooting – in pictures Florida shooting – in pictures Police arrest a suspect in connection with the shooting at the Marjory Stoneman Douglas High School in Parkland, Florida Reuters Florida shooting – in pictures Parents wait for news after reports of a shooting at Marjory Stoneman Douglas High School in Parkland, Florida AP Florida shooting – in pictures Anxious family members wait for news of students AP Photo/Wilfredo Lee Florida shooting – in pictures Students being evacuated from the school AP Florida shooting – in pictures Students being evacuated from the school Getty Florida shooting – in pictures People gather waiting for word from students AP Florida shooting – in pictures Parents waiting for news on their children AP Florida shooting – in pictures People gather at a hotel where students were taken after the shooting Getty Florida shooting – in pictures Florida Governor Rick Scott speaks to the media as he visits Marjory Stoneman Douglas High School following the shooting AFP/Getty Florida shooting – in pictures Dr. Igor Nichiporenko, Medical Director Trauma, left, and Dr. Evan Boyer, Medical Director, Emergency Services, speak about treating victims and the suspect at a press conference outside Broward Health North hospital AP

Democratic Senator Chris Murphy, a prominent advocate for gun control, had addressed the issue on the Senate floor on Wednesday. He had originally planned to discuss a separate issue, but spoke for several minutes on that day’s shooting.

“This happens nowhere else other than the United States of America – this epidemic of mass slaughter, this scourge of school shooting after school shooting,” said Mr Murphy, who represents the district where the Sandy Hook Elementary School shooting took place in 2012 where 26 people were killed.

He added: “It only happens here not because of coincidence, not because of bad luck, but as a consequence of our inaction. We are responsible.”

Gun violence has become a regular occurrence at US schools and universities. There has been an average of one school shooting per week since 2014, according to Everytown for Gun Safety, a research and advocacy group that lobbies the government for stricter gun control laws.