Millions of Canadians woke up to an emergency alert about an unspecified "incident" at a Toronto area nuclear plant that officials soon after said was sent by mistake Sunday.
The alert, which was sent to everyone in the province of Ontario just before 7:30 a.m. local time, warned that "an incident" was reported at the Pickering Nuclear Generating Station, but that there was "NO abnormal release of radioactivity" and that people in the immediate area did not need to take any protective measures.
A little over a half hour later, Ontario Power Generation, which operates the facility, tweeted that the alert was sent in error and that there was no danger to the public or the environment.
The power company said in a statement to BuzzFeed News that it was working with the local officials to investigate the incident, reiterating that "there is no danger to the public."
"There was no radiological event," the statement said. "The alert was issued in error."
Ontario Solicitor General Sylvia Jones later said that the erroneous alert was issued during a routine training exercise, adding that there was no incident that should have triggered the notification to the public.
A spokesperson for Jones' office told BuzzFeed News the alert was issued by staff at the provincial emergency operations center, a division of the Ministry of the Solicitor General.
"The Government of Ontario sincerely apologizes for raising public concern and has begun a full investigation to determine how this error happened and will take appropriate steps to ensure this doesn't happen again," Jones said in a statement on Twitter.
The alert caused panic across the province. Some people made references to the 1986 Chernobyl nuclear disaster in Ukraine, which was dramatized in an HBO miniseries last year.
And, as with just about any news event in times like these, people tweeted their jokes about the situation.
Almost two hours after the initial message, people received a second emergency alert that said the previous alert was issued in error and that there was "NO active nuclear situation" at the facility.
Pickering Mayor Dave Ryan said he is demanding a full investigation into how the mistake happened.
"Like many of you, I was very troubled to have received that emergency alert this morning," Ryan said in a tweet. "While I am relieved that there was no actual emergency, I am upset that an error such as this occurred."