Mr Devine said Metropolitan Fire Service crews attended and were investigating the cause of the incident with other authorities.
He said two people, who were sub-contracted by a private company that owns electrical assets at Tonsley, were injured in the incident. They were treated at the scene by SA Ambulance Service then taken to hospital for further treatment.
“Our thoughts are with the two injured people and their families.”
Mr Devine said power would be restored to the Main Assembly Building as soon as it was safe to do so.
He said emergency alarms in the MAB were activated by the incident immediately and the building was evacuated.
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