IS claims responsible for Orlando shooting, anti-terrorism under scrutiny in U.S.

ORLANDO, June 13, 2016 -- Highway-patrol troopers block the way to the mass shooting scene in Orlando, the United States, June 12, 2016. At least fifty people were killed and 53 others wounded early Sunday in a shooting spree at a gay nightclub in Orlando, Florida. (Xinhua/Yin Bogu)

BEIJING, June 13 -- Islamist militant group the Islamic State (IS) has claimed responsibility for the Orlando shooting in the U.S., prompting new scrutiny of anti-terror strategy by President Barack Obama and the presidential candidates.

At least 50 people were killed and 53 others wounded, including a police officer, early Sunday in the shooting at the popular gay nightclub Pulse in Orlando, Florida. It is the deadliest terror attack in U.S. history since the Sept 11 terror attacks in 2001.

No Chinese national has been found among the victims so far, the Chinese Consulate-General in Houston said.

IS-linked news agency Amaq said on Sunday that the Islamist militant group was responsible for the shooting. "The attack that targeted a nightclub for homosexuals in Orlando, Florida and left more than 100 dead and wounded was carried out by an Islamic State fighter," said Amaq in a short English statement that went online Sunday evening.

The gunman, identified by authorities as Omar Mateen of Port St. Lucie, Florida, was found dead inside the nightclub after a shootout with the police.

The shooting began around 2:00 a.m. local time (0600 GMT) inside the nightclub and there once was a confrontation between the suspect and an officer working at the club outside the venue, according to local police.

Then the suspect went back into the club to continue shooting and took hostages.

About three hours after the shooting first broke out, police shot and killed the suspect during actions to rescue the hostages.

"It appeared he was organized and well-prepared," said Orlando Police Chief John Mina at an earlier press conference, adding that the suspect had an assault-type weapon and a handgun.

President Obama on Sunday called the mass shooting an "act of terror" and "act of hate." His statement marked at least the 20th time he had addressed the nation on the topic of mass shooting during his presidency.

Calling the Florida shooting spree "the most deadly shooting in American history," Obama reminded U.S. citizens of the sober reality that "how easy it is for someone to get their hands on a weapon" that could launch mass killings.

The Obama administration initiated stronger gun control laws in 2012 but failed to push through in Congress after staunch opposition from Republican lawmakers and gun-rights lobby groups.

In an interview last year Obama called the failure to reform U.S. gun laws "one of the greatest frustrations" of his presidency.

Presidential candidates Donald Trump and Hillary Clinton both adjusted their presidential politicking Sunday, offering prayers and support to the victims.

Clinton pushed for gun control and reached out to gays and lesbians, a key constituency.

"The gunman attacked an LGBT nightclub during Pride Month. To the LGBT community: please know that you have millions of allies across our country. I am one of them," she said in a statement, adding a call to keep assault weapons out of the hands of "terrorists or other violent criminals." Republican nominee Trump also offered words of support. On Twitter, he renewed talk of his plan to ban Muslims from the U.S. for an indeterminate time.

"Is President Obama going to finally mention the words radical Islamic terrorism? If he doesn't he should immediately resign in disgrace!" Trump tweeted.

Trump has proposed temporarily barring all foreign Muslims from entering the country and has advocated using waterboarding and other harsh interrogation methods.

The shootings also inspired the candidates to shift their schedules and focus.

Clinton's presidential campaign announced it was postponing its first joint event with Obama on Wednesday because of the terror shooting.

Trump said he was changing the focus of his speech Monday at Saint Anselm College in New Hampshire from his case against Clinton to "this terrorist attack, immigration and national security."