A driver suffered head and chest injuries following a head-on crash.
The accident happened in Capel Road, Rusper, near Horsham, shortly after 6.30pm on Friday.
Firefighters from Crawley were needed to help cut the man free from his car and he was treated at the scene before being taken to East Surrey Hospital in Redhill.
The other car driver was unhurt.
The road was closed while emergency services dealt with the scene.
Witnesses are asked to contact Sussex Police on 101.
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