A man dressed as Zorro wearing a black cape and plastic sword was arrested in the moments before one of America's biggest airports was frantically evacuated.

Reports of an 'active shooter' inside a terminal at LAX resulted in thousands of travellers being ushered on to the tarmac.

But less than half an hour later, emergency services gave the 'all clear' and directed the distressed passengers back inside.

View photos Travellers crowd around planes on the runway amid reports of active shooter. Photo: Ross Greenberg More

Just ran for my life at #lax people screaming "active shooter". Followed TSA personnel to safety — Ross Greenberg (@Rossegreenberg) August 29, 2016

Video has emerged of the moments before the scare, as police surround a man wearing a black cape and hat as he sits on a chair outside the building.

Six officers and a police dog inch towards the man, who is instructed to move away from his plastic sword and lie on the ground.

It is unclear if he is connected to the evacuation.

View photos Six officers and a police dog surrounded the man dressed as 'Zorro' outside the terminal. Photo: Sam Macon More

View photos The man was arrested in the moments before the evacuation. Photo: Sam Macon More

Early reports stated that shots were fired in terminal 8, but police have denied the claims.

Commanding officer of LAPD media relations Andy Neiman tweeted that no shots were fired.

"Report of shooting at LAX proven to be LOUD NOISES only no shots fired no injuries investigation continues to locate source," he wrote on Twitter.

Active #shooter in #LAX. We all had to run out. We're standing on the tarmac waiting for instructions. pic.twitter.com/mxCDxXfPOL — Douglas Lee (@twitta_D) August 29, 2016

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