A SOUTHAMPTON man has admitted to speeding on the M3 and M25 when a 50mph speed limit was in place. 

Mark Johnstone of Bury Road, Marchwood admitted a single charge of exceeding a 50mph speed restriction on a special road or motorway. 

The 46-year-old Mercedes driver was caught above the limit on the M3 between junction 2 and 4a and the M25 at junction 12. 

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He was spotted on October 10 last year. The stretch is a smart motorway with variable speed limits.

Johnstone pleaded guilty on April 20 this year at Guildford Magistrates' Court. 

The case was adjourned until May 25.