A man has survived being pushed onto a 750-volt live track at a crowded railway station after trying to defuse a violent argument.
The 46-year-old was standing at Portsmouth and Southsea station late last night when he saw another man punched in an unprovoked attack.
He stepped in to try and calm the situation on the busy platform but was pushed onto the tracks by the attacker.
Detective Constable Phil James, from British Transport Police (BTP) said: "I cannot emphasise how dangerous this assault was. The man, who bravely stepped in to calm a heated situation, came very close to the 750-volt live rail and was quite understandably left very shaken as a result."
The 29-year-old man from Havant in Hampshire was standing on the platform with a friend when he was approached by the attacker aged around 25 and punched in the face.
In a bid to calm the situation, the Good Samaritan from Chichester in West Sussex, who was waiting on the platform, stepped in to defuse the fight.
"The suspect then suddenly pushed the man onto the rail tracks," DC James said.
The attacker was described as of skinny build with dark scruffy hair and about 5'10 in height and wearing a faded purple zipped-up hooded-top.
The pushed man need hospital treatment for a cut head but was otherwise unhurt.
BTP said officers were now examining CCTV footage to try and identify the man.
"The incident took place on a crowded platform so therefore I am certain that there are witnesses that will have information to assist our investigation.
"If you have any information about this attack, we want to hear from you," added the officer.