Police and ambulance services have been called to what is believed to be a medical incident in Horsham town centre, according to an eyewitness.
The witness reported seeing an ambulance, two cars and a critical care team.
They also saw a police vehicle attending.
Another reader contacted the County Times to say a helicopter, believed to be an air ambulance, landed in the area.
A spokesman for the air ambulance said they were called to an incident in the town at around 12:30pm today (Friday June 6)