The sickening ordeal happened after the teenager got into a car on Blackpool Promenade and was driven to a nearby house. She was then brutally raped by as many as five men.
The local girl is thought to have got into a silver Vauxhall Astra voluntarily before she was bundled into the house and repeatedly raped. Two hours after the incident began she was released by her attackers. She made it to a friend's house and called police.
A team of 10 detectives is now working to catch the gang behind Tuesday night's assault.
Det Insp Tim Leeson, of Blackpool CID, said: "This was a sickening sexual assault on a teenager who was tricked into going with her attackers.
"We believe she got into the car of her own free will, but was lured in under false pretences. She was driven to a house in Blackpool where she was the victim of a prolonged sexual attack.
"We believe she was raped for nearly two hours.
"This was an extremely nasty attack which we are taking very seriously and we have our best detectives working on the case.
"We are appealing for anyone who was on The Promenade between Central and North Pier on Tuesday night to come forward and speak to us.
"No matter how small or insignificant a piece of
information may seem, we need to know about it
because it could help."
Within 24 hours of the
attack, which began when the girl was picked up on The Prom at 9pm, detectives arrested five men in the Blackpool area.
They were detained at Bonny Street police station and officers were granted a 36-hour extension by magistrates yesterday to further question the suspects. Officers have until 8am tomorrow to continue their inquiries before the men have to be charged or released.
Anyone with information is asked to contact Blackpool Police on (01253) 293933 or Crimestoppers on 0800 555111 quoting crime number 70WQ180505.