Fire Brigades Union general secretary Matt Wrack said:
"Firefighters at the Apollo Theatre were fantastic in their response to an incident that could have seen significant loss of life, but we're sick of being praised by politicians one minute and stabbed in the back the next.
"Our world-class fire and rescue service is being devastated by the worst cuts in our history, cuts that prevent firefighters from doing their jobs during day-to-day emergencies, major incidents like the Apollo Theatre or Clutha Bar collapses and recent floods and storms."
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The Tooting MP has been the frontrunner in the counting process ahead of Tory challenger Zac Goldsmith.
It's not just London where elections have been taking place today. There were council elections taking place across the home counties.
A list of results for London Mayor and the London Assembly