Fifty people have been killed, including the assailant, and at least 53 injured in an attack inside a gay nightclub in Orlando, in the US state of Florida, according to police.
Officials said on Sunday morning that the shooter, who was armed with assault-type rifle, handgun and some type of other device, died in a shootout with the police force at the Pulse nightclub.
US news networks have identified the gunman as a New York-born resident of Florida with Afghan origins. But police have yet to make an official announcement.
The injured had been transferred to nearby hospitals, police said.
John Mina, Orlando police chief, said: "This did turn into a hostage situation. At approximately 05:00 hours (09:00 GMT) this morning, the decision was made to rescue hostages that were in there."
In a statement, the White House press office said US President Barack Obama was briefed of the incident by Lisa Monaco, top advisor for Homeland Security and Counterterrorism.
Florida authorities said the attack was being treated as an "act of domestic or international terrorism".
"We are investigating this from all parties' perspective as an act of terrorism," said Danny Banks, special agent in charge of the Florida Department of Law Enforcement.
"Whether that is domestic terrorist activity or an international one, that is something we will certainly get to the bottom of," he added.
Officials said on Sunday morning that the shooter, who was armed with assault-type rifle, handgun and some type of other device, died in a shootout with the police force at the Pulse nightclub.
US news networks have identified the gunman as a New York-born resident of Florida with Afghan origins. But police have yet to make an official announcement.
The injured had been transferred to nearby hospitals, police said.
John Mina, Orlando police chief, said: "This did turn into a hostage situation. At approximately 05:00 hours (09:00 GMT) this morning, the decision was made to rescue hostages that were in there."
In a statement, the White House press office said US President Barack Obama was briefed of the incident by Lisa Monaco, top advisor for Homeland Security and Counterterrorism.
Florida authorities said the attack was being treated as an "act of domestic or international terrorism".
"We are investigating this from all parties' perspective as an act of terrorism," said Danny Banks, special agent in charge of the Florida Department of Law Enforcement.
"Whether that is domestic terrorist activity or an international one, that is something we will certainly get to the bottom of," he added.
