Part of a major route in Suffolk was blocked after emergency services were called to a two-vehicle crash.
Police were alerted to the crash in the A143 near Rickinghall at about 2pm on Sunday.
A spokeswoman for Suffolk police said a red Audi and blue Volvo were involved in the crash.
Suffolk Police have now confirmed that a male in his 40s was arrested on suspicion of driving with excessive drugs in his system.
He was taken to hospital for initial treatment and was then taken into police custody.
He has now been released and is under investigation, pending further enquiries.
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