Pride organiser John Bird described the attack on two men in Liverpool as "terrifying".
The 60 plants had a potential annual yield of about £250,000, police said.
News, sport, travel and weather updates from across the North West of England on Tuesday 25 June
Briton Liam Smith says younger brother Callum can beat Saul 'Canelo' Alvarez if they can agree a bout.
Tranmere Rovers sign central defender George Ray, who rejected a deal to stay with Crewe Alexandra, on a two-year deal.
Runcorn and Widnes World
St. Helens Star
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How divers pulled off the rescue of the century.
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