A teenager, who is not a pupil at the school, is being held for questioning by police.
Jamal Powell suffered multiple knife wounds at the Blue Mountain Club in Bristol last December.
The council said there were "unforeseen problems" at the Temple Circus junction, with unrecorded electricity cables and water pipes.
The event was the culmination of two weeks of events celebrating LGBT diversity in the city.
John Volanthen said the team of divers located the boys due to the smell in the flooded cave in Thailand.
Gloucestershire host Sussex in the County Championship - listen to BBC local radio commentary from Cheltenham.
Injured Gloucestershire bowler Liam Norwell and batsman George Hankins will miss the remainder of the season.
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How did this Welsh drama become such a huge hit?
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