At around 6.55pm on Wednesday 3 February 2021, officers were called by South East Coast Ambulance Service to a report of a man with injuries consistent with a stab wound in Week Street at its junction with the High Street.
Officers attended the scene where the man received medical attention before being taken to a London hospital for treatment to injuries that are described as life threatening.
A second man who is also thought to have been injured had left the scene before the attendance of emergency services and officers are urging him to contact Kent Police at his earliest opportunity.
A suspect in his 40s has been arrested in connection with the incident and been taken into custody.
A cordon is currently in place at the scene and investigators are appealing for witnesses to the incident, or anybody with information, to call the appeal line on call 01622 604100, quoting reference 3-1151.
You can also contact the independent charity Crimestoppers, anonymously, on 0800 555 111 or by using the anonymous online form.