Sussex Police Assistant Chief Constable Steve Barry said police had identified 11 people they were treating as “highly likely to have died in this tragedy”.
Mr Barry also warned that the death toll could rise further still.
Investigators are keeping “an open mind” about who has been involved in the crash as they continue to receive calls from worried friends and relatives.
He said: “The scene itself is incredibly large. A lot of specially-trained officers are sifting, as we speak, so we do need to keep an open mind but from what we have seen at this stage it is possible that we will find more fatalities.”
He added they could not yet formally identify any of those who had died.
Mr Barry said: “This has been an enormously traumatic incident and our thoughts are with everyone who has been affected, from those who have suffered bereavement to those in the local community who are deeply shocked.”
He added: “Sadly, as a result of our initial work at the site, which has continued overnight, and inquiries following calls to the emergency services from worried families and friends, we have now identified 11 people who we are treating as highly likely to have died in this tragedy.”
Explaining why he could not say for certain that 11 people had died, Mr Barry said it was a “technical process” which needs help from the next of kin to identify any of the bodies which are recovered.
He said: “At the moment, it may be conjecture.
“We work really closely with the families and we have specially-trained officers giving the most up-to-date information to the families that helps inform us and effectively classifies them as highly likely as having died in the crash.
“It is not until the body is recovered that we are able to fully identify who has been killed.”
Although police have not formally identified any of the victims, families have named some, including Matt Jones, 24, and Worthing United FC footballer Matthew Grimstone, 23.
Another Worthing United footballer, Jacob Schilt, 23, is also believed to be among the victims, his club said yesterday.
Specialists from other police forces in the South East and the West Sussex Fire and Rescue Service have been drafted into help with the recovery operation, and Mr Barry said the removal of the bodies will continue throughout today.
A crane will also be brought in to lift the wreckage of the aircraft today, when police fear they may discover more dead.An exclusion zone last night remained in place around the crash site, which is a hazardous area after investigators discovered there was still fuel on the plane.
Mr Barry said the status of the jet’s ejector seats was yet to be determined but confirmed the pilot was pulled from the burning wreckage.
He said: “The pilot who was freed from the wreckage remains in a critical condition in the Royal Sussex County Hospital in Brighton. Others who were injured have all now been treated for their injuries.”
Mr Barry also said that speaking with the pilot was vitally important to their investigation, saying: “That will be a key avenue, that we would like to talk to the pilot and establish what occurred.”
He added: “It is quite clear what has occurred, but what we need to establish through the investigation is why it occurred.”
Mr Barry said the crash site was spread over an “extremely large area” covering about 400 yards on the Shoreham airfield itself.
He also said: “We know nobody that was attending the air show was injured but we do fear that when we start to recover the victims we will find there are more fatalities.”
Meanwhile in northern Switzerland yesterday, at least one person was killed after two small planes collided in mid-air.