The men were from the Brighton area, aged between 25 and 30 and had boarded a breakdown recovery van after their minibus has broken down on the M1.
The vehicle collided with a lorry between junction 8 at Reigate and Junction 9 at Leatherhead. The 46-year-old recovery van driver, from Rugby, also died.
The only survivor from the crash is in a stable condition in an East Surrey hospital with leg and facial injuries.
Chief Superintendent Rob Price from Surrey police confirmed that the investigation into what happened will take some time.
"A thorough investigation is being undertaken by the Surrey police collision investigation team and it will be a number of days before we will be in a position to release further details," he said.
"Our thoughts are very much with the families and friends of the six people who died in this tragic crash. This is one of the worst collisions Surrey police has dealt with on the M25. At this stage it is too early to confirm the exact cause of the collision."
Dunchurch Motors, which dispatched the recovery vehicle, said it could not comment any further on the crash but said its thoughts were with the family of its driver and the families of those who died.
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