Authorities on June 13 were investigating whether a gunman who killed 49 people at a gay nightclub in Orlando and declared his allegiance to Islamic State militants had received any help in carrying out the massacre.
The FBI and other agencies were looking at evidence inside and in the closed-off streets around the Pulse nightclub, where New York-born Omar Mateen perpetrated the deadliest mass shooting in U.S. history, and the worst attack on U.S. soil since the Sept. 11, 2001.
Mateen, the 29-year-old son of Afghan immigrants, was shot and killed by police who stormed the club early June 12 with armored cars after a three-hour siege.
Law enforcement officials were looking for clues as to whether anyone had worked with Mateen on the attack, said Lee Bentley, the U.S. attorney for the middle district of Florida.
"There is an investigation of other persons. We are working as diligently as we can on that," Bentley said at a news conference. "If anyone else was involved in this crime, they will be prosecuted."
Officials stressed they believed there had been no other attackers and had no evidence of a threat to the public.
Mateen's rampage began about 2 a.m. June 12, when the club was packed with some 350 revelers. Many fled as the gunman raked the crowd with bullets from an AR-15-style semiautomatic rifle and a pistol.
An initial wave of officers charged into the club and trapped Mateen in a bathroom, Orlando Police Chief John Mina told reporters. That action allowed many patrons to flee, although others were trapped in the restroom with Mateen, leading to the standoff.
"We were able to save and rescue dozens and dozens of people," Mina said. Police negotiated with Mateen for about three hours before breaking a hole in the wall, which allowed hostages to escape.
Mateen also emerged from the hole and was shot dead by officers, police said.
Officials said on June 12 the death toll was 50. On June 13, they clarified that the figure included Mateen. Some 53 people were wounded and 29 remain hospitalized at Orlando Regional Medical Center, the hospital said on Twitter.
'HAVEN'T HEARD ANYTHING'
By the morning of June 13, all but one of those killed had been identified and about half the families of the dead had been notified, officials said.
Other family members were desperate for news about their missing loved ones.
Julissa Leal, 18, and her mother drove to the Florida city from Lafayette, Louisiana, in search of her brother, 27-year-old Frank Hernandez. They knew he was at the club with his boyfriend, who lost him in the chaos.
"We haven't heard anything, don't know anything," Leal said, fighting back tears. "I'm going to see him again. I'm going to see him again."
Mateen called emergency services during the shooting and pledged allegiance to the leader of the militant Islamic State group, officials said.
Mateen's father said his son was not radicalized but indicated the gunman had strong anti-gay feelings.
Mateen's ex-wife described him as mentally unstable and violent toward her.
Islamic State reiterated on June 13 a claim of responsibility. "One of the Caliphate's soldiers in America carried out a security invasion where he was able to enter a crusader gathering at a nightclub for homosexuals in Orlando," the group said in a broadcast on its Albayan Radio.
The group's claim of responsibility does not mean it directed the attack, as it offered nothing to indicate coordination with the gunman.
CANDIDATES DEBATE RESPONSE
President Barack Obama denounced the attack as an act of terror and hate and said on June 13 that the gunman seemed to have been inspired by extremist ideas.
"It appears that the shooter was inspired by various extremist information that was disseminated over the internet," Obama told reporters at the White House. "It does appear that at the last minute he announced allegiance to ISIL (Islamic State), but there is no direct evidence so far that he was directed."
The attack reignited the debate over how best to confront violent Islamist militancy, and immediately became a sharp point of disagreement in the campaign for the Nov. 8 presidential election.
Democratic candidate Hillary Clinton, speaking on MSNBC, said the United States should walk a fine line in bolstering security without demonizing Muslims, and also called for tougher gun safety measures.
Wealthy businessman and presumptive Republican nominee Donald Trump, in interviews with CNN and Fox News, criticized the U.S. Muslim population for not reporting suspicions to authorities, and reiterated his call for a temporary ban on Muslims entering the country.
The carnage early on June 12 occurred in the heart of Orlando, about 15 miles northeast of the Walt Disney World Resort. The city is one of the most popular tourist destinations in the country, drawing some 62 million visitors a year.
FATHER: 'I DON'T FORGIVE HIM'
Mateen was an armed guard at a gated retirement community and had worked for a global security firm for nine years. He had cleared two company background screenings, the latest in 2013, according to G4S, the firm.
Mateen’s father, Seddique Mir Mateen, said in an interview at his home in Port Saint Lucie, Florida, that he was angered by his son’s actions.
"Even though he is my son I admit this is terrorist act. This is terrorizing. I don't forgive him," the father said. "If you see his wife, what she is going through his poor wife and his son 3-1/12 years old, such a nice son, he should've thought about that."
Mateen's former wife, Sitora Yusufiy, told reporters near Boulder, Colorado, that she had been beaten by Mateen during angry outbursts in which he would "express hatred towards everything."
Authorities said on June 12 that Mateen had been twice questioned by FBI agents in 2013 and 2014 after making comments to co-workers about supporting militant groups, but neither interview led to evidence of criminal activity.
Mateen visited Saudi Arabia in 2011 and 2012 for religious pilgrimages, a government spokesman said.
The attack in Orlando came six months after a married couple in California — a U.S.-born son of Pakistani immigrants and a Pakistani-born woman he married in Saudi Arabia — killed 14 people at an office holiday party in San Bernardino. The couple, who were inspired by Islamic State, died in a shootout with police hours after the mass shooting.
The most deadly attack on the nation's soil inspired by violent Islamist militancy was on Sept. 11, 2001, when al Qaeda-trained hijackers crashed jetliners into New York's World Trade Center, the Pentagon and a field in Pennsylvania, killing some 3,000 people.
Additional reporting by Barbara Liston and Yara Bayoumy in Fort Pierce, Fla., Zachary Fagenson in Port St. Lucie, Fla., Omar Fahmy in Cairo, Michelle Martin in Berlin and Susan Heavey, Caren Bohan, David Alexander and Jonathan Landay in Washington; Writing by Roberta Rampton and Scott Malone.