Three other people were arrested in Tottenham, north London, at the same time as McLoughlin, police said.
The 54-year-old man from Tottenham, 45-year-old woman from Edmonton, north London, and 50-year-old man from Hackney were arrested on suspicion of assisting an offender.
All four are being questioned at Hatfield police station, Hertfordshire Police said.
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Camden Council is evacuating five tower in the Chalcots estate in north London, to allow "urgent fire safety works" to take place.
Scotland Yard said it was taking action under public order laws over the marches "due to concerns of serious public disorder".
The Football Association says it is hoped that the match will raise around £1.25million for the victims.