David Cameron appeared to be pushed by a man after giving a speech in Leeds about new high-speed rail plans in the north of the country (HS3).
Footage after the event showed a man running up to the prime minister in the street outside Civic Hall and briefly coming into contact with him.
While it appears to be a surprising breach, the man seemed to offer no resistance when grabbed by security officials and Cameron appeared relaxed when getting into his car.
Police said a 28-year-old local man had been arrested and de-arrested, meaning no further action will be taken and the record of the arrest itself will be expunged.
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