Detectives hunting those responsible for the drone shutdown that caused chaos at Gatwick airport have admitted they are no closer to finding them.
Some 150,000 people were left stranded when all planes were grounded for 33 hours at the peak of the Christmas getaway.
He admitted the force still does not have a picture or footage of the device spotted by 115 witnesses and does not know the make or model.
Mr York also apologised to Paul Gait and Elaine Kirk, the couple arrested and released without charge after three days amid intense media scrutiny.
“I don’t think we have found the drone responsible,” he told BBC Radio 4’s Today programme.
But he added: “We’re getting closer to being able to identify the model. There have been 115 reports of seeing drones in the area.
“We live in an age where everybody now expects us to be able to produce a high-quality image or video footage of what was going on but that hasn’t been available because of the times of flights, sometimes the speed that it was doing.”
Different people had claimed it was different models, Mr York said.
Referring to comments by a police colleague after flights had resumed that there may never have been a drone at all, he said: “I’m absolutely certain that there was a drone flying through the period that the airport was closed.
“I spoke to an eyewitness yesterday who was on the roof of the airport, with four other people seeing it, and what they saw was corroborated by two police officers near the runway.”
He said 92 of the 115 reports were from people police had confirmed were credible.
Sussex Police launched their own drone to investigate, which could have confused some witnesses as well, Mr York believed. And some of the sightings of drones may have involved the police's own craft, he admitted.
During the busiest week of the winter, Gatwick airport was closed for 33 hours.
The initial shutdown began at 9pm on Wednesday 19 December and continued to 6am on Friday 21 December.
Gatwick has the busiest runway in the world, and around 1,000 flights were cancelled, affecting at least 150,000 passengers.
While European air passengers’ rights rules stipulate a duty of care to stranded travellers, the number of people sleeping on the floor at Gatwick showed that not all airlines were following the regulations.
As Sussex Police came under intense scrutiny over their handling of the mystery drone or drones, detectives arrested Mr Gait and Ms Kirk, from Crawley, near Gatwick, although his employer later gave him a solid alibi.
Mr York justified the arrests of the couple who had been held without charge by saying: “The grounds for an arrest is reasonable suspicion.
“I absolutely understand where Paul is coming from and how he feels and the way they have been made very public over the weekend in the middle of this.
“I’m convinced that the grounds for the arrest, the lawful suspicion in the first instance, are well founded.”
When asked to apologise, Mr York said: “I’m really sorry for what he’s experiencing, the feeling of violation around it.
“I am really sorry for what he went through but the reason we held him was so that we could dispel everything in the first instance.
“What might have been worse an experience for them would have been to be released under investigation still.”
Mr York explained the holding of Mr Gait and Ms Kirk for three days by saying taking time allowed Mr Gait “the best opportunity to put his life back on the rails”.
Critics said the apology sounded like an empty one. One Twitter user wrote Sussex Police ”should be ashamed embarrassed and sued... the police have identified people before things have been investigated.”
Another said police had been “panicked” into making arrests, “probably under pressure from the Home Office”. A third said he was disgusted by police “lack of competence”.
Confirming that military technology had been put in place at Gatwick to prevent further drone disruption, Mr York said: “The systems in place today are dramatically different from those in place a week ago.”
On Monday, security minister Ben Wallace issued a cryptic statement saying drone defence systems “could now be used” across the UK. He did not clarify whether that meant technology had been installed, and if so where, or whether it meant a deal to install it had been reached, or how widespread.
Mr York said it was impossible to rule out a similar case happening in future, but added: “What’s at the heart of this is ensuring it’s safe for aircraft to take off and that is the different position that Gatwick airport finds itself in today and many others will be able to say ‘Yes, it’s now safe for aircraft to take off again’.”
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