Highways England reported the northbound stretch from junction 2 at Tipner to junction 1 Rudmore was ‘closed due to a police incident’ at 9.05am.
Meanwhile Portsmouth Roads, posting on social media, said: ‘Police dealing with pedestrian on the carriageway.’
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The M275 then partially opened with lane one still closed at 9.10am before it was reported the carriageway was now ‘fully open’ at 9.40am.