A gunman opened fire from 32nd floor of the Mandala Bay Hotel toward a crowd gathered together for an open-air music festival in Las Vegas. At least 20 were killed and more than 100 wounded.

Las Vegas police identified the attacker, saying that he is a local man but declined to release the identity.

The police is searching for a 61 year-old women named Marilou Danley in connection with the attack. Danley was seen travelling with the attacker prior to the shooting.

Los Angeles Sheriff Joseph Lombardo said 20 were killed and more than 100 wounded in the shooting. The attacker was killed in the hotel room where he shot on the crowd by the police.

Lombardo said they believe that the attacker is a “lone wolf type actor” but the police is evaluating reports of multiple attackers.

Authorities said one on-duty officer in critical condition and another was wounded in the shooting. Two off-duty police officers attending the concert were killed.

Country singer Jason Aldean was performing during the Route 91 Harvest Festival when gunfire erupted. Aldean said he and his crew are safe in a statement.

"Tonight has been beyond horrific. I still don't know what to say but wanted to let everyone know that me and my crew are safe. My thoughts and prayers go out to everyone involved tonight. It hurts my heart that this would happen to anyone who was just coming out to enjoy what should have been a fun night" he wrote on Instagram. 

The area is locked down by the police. All clubs and businesses on the strip are closed.