Four men and a teenager have been arrested by officers in connection with the incident. Two are still being held on suspicion of attempted murder.
Police were called to the scene at 6.10am and the man, who is believed to be in his 20s, was treated by paramedics before being taken to a London hospital. It is not known how long he had been there before being found.
Following enquiries, a 28-year-old local man was arrested later that day in Tonbridge on suspicion of assisting offenders.
The next day, officers made further arrests in Folkestone. On Tram Road, they arrested a 20-year-old man from the town and a 16-year-old boy from Dover on suspicion of attempted murder. All three have been released pending further investigation.
Later on the Sunday, patrols also picked up two men from the area, aged 24 and 33, on Road of Remembrance and Marine Terrace, also on suspicion of attempted murder. They remain in custody.
Detective Inspector Jon Faulkner of Kent Police said: “While my officers have made a number of arrests, we are keen to hear from anyone who may have witnessed the incident or has any information that will help the investigation.”
The public are asked to call 01622 604100 quoting crime reference 30-311, or contact the independent charity Crimestoppers anonymously on 0800 555111.
The incident is the latest in a series of attacks in and around the town, as Kent Police wage a campaign to stop the escalation in violent crime.
The night before the latest attack, officers apprehended a 16-year-old boy after he was found with a kitchen knife during a sniffer dog operation to search for drugs at Tonbridge railway station.
The youth was stopped and charged after crossing the road to evade the police.
Last month a 19-year-old man was stabbed in Vale Road, and police arrested a man from Tonbridge who was the same age and a 21-year-old man from Hastings who have been released on bail.
And a teenager was sentenced to a year in prison on March 21 after threatening to use a knife twice inside a fortnight.
Bailey White was arrested twice this year after claims he threatened to harm another teenager on two separate occasions.
The 18-year-old from north Kent pleaded guilty to two counts of possessing an offensive weapon in a public place.
The case calls into question the effectiveness of the force’s ‘zero tolerance policy’ because White reoffended while he was on bail.
After the second court appearance he was remanded in custody until his sentencing.
White was first arrested on January 24 after patrols stopped a BMW he was travelling in on the A26 in Southborough.
The car was pulled over after police received a report that White had threatened a boy with a knife in Hadlow earlier that day.
A search uncovered a large knife, with a six-inch long blade. White was charged with possessing an offensive weapon and bailed to attend Sevenoaks Magistrates’ Court on March 5.
But he was arrested again while he was waiting at McDonald’s drive-through restaurant in Cannon Lane at 2am on February 11.
The police acted on a report that White had threatened to assault the same victim the previous day. He was again found with a knife, this time with a five-inch blade.
At Medway Magistrates’ Court the next day he pleaded guilty to the offences and this time was remanded in custody.
Police Constable Levi Caruana, the investigating office, said: “This case is a clear example of Kent Police taking a zero tolerance approach towards people who chose to carry a knife in a public place.
“White was promptly arrested when we received an allegation he had threatened someone with a weapon but, despite being charged and bailed for the offence, he chose to re-offend.
“His decision to continue carrying a knife endangered himself and other members of the public and it is entirely appropriate that we worked quickly with the Crown Prosecution Service and local courts to secure an immediate custodial sentence.”
Last month it was announced that 1,200 extra officers in Kent will now carry Tasers to fight violent crime.
Incidents involving knives have increased at the fastest rate of any county in England, more than doubling in the past eight years.