A man has been arrested at a Heathrow Airport train station in relation to a knife attack on a 63-year-old man at Finsbury Park Tube.
He was held by officers after they found him at the Heathrow 1,2,3 Underground station on Tuesday afternoon.
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The victim received cuts to his body and face but it is thought he will recover.
A manhunt across the Tube network was launched after the incident, in which witnesses described hearing an argument before the attack.
A British Transport Police (BTP) spokesman said: "A man has been arrested at Heathrow Terminals 1,2,3 Underground station on suspicion of GBH after a man was assaulted at Finsbury Park Underground station on Tuesday, 11 August.
"British Transport Police (BTP) detectives will be speaking to the man in due course.
"The assault occurred on the southbound Victoria line platform shortly before 1.45pm. A 63-year-old man was taken to hospital with cuts to his body and face. His injuries are not thought to be life-threatening.
"Armed BTP officers searching for a possible suspect met a southbound Victoria line train at King's Cross St Pancras Underground station at approximately 3pm."
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