The unintended release of an Ontario-wide alert about an "incident" at the Pickering Nuclear Generating Station has sparked a provincial investigation. The investigation will be looking into how such an error could happen and how such future mistakes can be avoided. The province's solicitor general said the error occurred during a routine training exercise being conducted by the Provincial Emergency Operations Centre. The PEOC is responsible for co-ordinating the provincial government's response to major emergencies. Solicitor General Sylvia Jones said the agency conducts exercises testing the system twice daily, but there was no intention to notify the public. Jones said the investigation will examine the sequence of events that led to the alert being sent out and what contingency measures should be in place. She expects that the results of the probe will be made public. The alert was pushed to cellphones, radios and TVs across the province at about 7:30 a.m. Ontario Power Generation, which oversees the Pickering plant, sent out a tweet about 40 minutes after the emergency alert saying it was a mistake. A follow-up alert was sent to cellphones nearly two hours after the original notification, and about an hour after the OPG tweet. Jones said it took so long to send a second alert because the province felt it needed to "trust, but confirm" that there really was no impending disaster.