Five serious crashes in 12 hours, including one in Horsham, have prompted West Sussex Fire and Rescue to issue a safety warning.
Drivers are being urged to avoid the ‘fatal four’ - the four most common causes of road accidents in the UK.
Two people were injured in the crash on the A24, a spokesman for South East Coast Ambulance said.
He added: “Three patients were assessed on scene and two were taken to East Surrey Hospital, Redhill.
“One with minor injuries and the other with a chest injury.”
The road was closed by police for around two hours due to the collision.
Two fire engines from Horsham and the heavy rescue tender from Worthing attended the scene.
There was also a crash involving a car and an articulated lorry on the M23 and serious collisions on the A27 between Chichester and Havant, in Henley and in Pagham.
The fatal four are inappropriate speed, using a mobile phone while driving, not wearing a seatbelt and drink/drug driving, a spokeswoman for the fire service said.
Motorists are also being urged to carry out basic vehicle checks, such as checking tread depth and tyre pressure.
Adrian Murphy, area manager for protection at West Sussex Fire And Rescue Service, said: “It was a busy end to the weekend for our crews and the other emergency services.
“Please take care on the roads so we can avoid a repeat of the number of incidents we have experienced.
“It so important that people are aware and remind themselves about the ‘fatal four’ - speed, distraction, seatbelts and drink and drug use. It’s not worth the risk.”