Police are appealing for witnesses following a serious accident on the A140 at Thornham Magna last night.
Emergency services were called to a two car collision, involving a blue Nissan Almera and a blue Vauxhall Zafira, at 5.30pm.
The road was closed and diversions put in place while the crash was dealt with. It reopened around 9.20pm.
Three people in the Vauxhall were injured, a man driver and two teenage boys, one of whom was seriously hurt.
The driver of the Nissan was also injured.
All were taken to hospital.
A fire crew from Eye and two from Diss attended the incident and used hydraulic rescue equipment to release an elderly man.
Police would like to hear from anyone who had been travelling along the A140 or who was in the area and saw the vehicles before, or when, the collision took place.
Calls should be made to Pc John Clarke at Suffolk Police Headquarters Roads Policing and Firearms Operations Unit on 101.