A FALSE alarm and evacuation order triggered by a small fire in a food outlet have caused dramatic scenes during the Collingwood-Adelaide clash at the MCG.
Less than one minute into the second quarter, a message was played over the stadium's loudspeakers instructing all patrons to immediately leave the venue.
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Umpires stopped the match and players gathered in team huddles in the middle of the ground as confused fans began heading for the exits.
A few minutes later, a second message was played to clarify it was a false alarm.
The MCC released a statement confirming fans were never in serious danger.
"The MCG emergency evacuation system was automatically triggered in a food outlet on level four of the Ponsford Stand," the statement said.
"An investigation into the issue was immediately commenced and no evidence of risk to patrons was detected.
"Venue management was able to stop the evacuation procedure and allow patrons back into the venue after approximately five minutes.
"The MCC sincerely apologises for the inconvenience to patrons and the competing clubs."
They explained the incident in further detail post-match.
"What we know at this stage is that during the course of usual operations, a sprinkler activated in a food outlet on Level 4 of the Ponsford Stand, towards the end of the quarter-time break. The water from the sprinkler hit an oven which was in use, creating steam," the statement read.
"As part of our standard safety procedures, the operation of a sprinkler activates the Emergency Evacuation System. In usual circumstances, once an incident of this nature is investigated and found to have no risk to patrons, the alarm system is isolated by our operators and the automated evacuation procedure is suspended.
"The MCC will conduct a full review of the operating system, to understand why the automated evacuation of the venue was not suspended."
This is not the first time a false alarm has shocked MCG patrons.
In 2015, an emergency siren sounded moments before the second half began in a Geelong-Richmond match.
It was caused by a fan's football hitting a sprinkler in the Ponsford Stand.