BARRIE, ONT. -- The Simcoe Muskoka health unit reports nine new COVID-19 cases on Tuesday.

Six Barrie men, all under the age of 34, a Bradford woman, 35 to 44, an Orillia senior woman and Orillia man 45 to 64, are the latest to be diagnosed with the virus.

On Monday, there was a massive lineup of vehicles at the drive-thru assessment clinic at Barrie's Royal Victoria Regional Health Centre.

The drive-thru clinic carried out a record number of COVID tests in a single day yesterday, with 356 swab tests.

Dr. Barry Pakes, a public health physician with the University of Toronto, who is currently working at a Barrie assessment centre, said testing typically ramps up after a weekend.

"We're certainly seeing lots of people who have been at cottages over the weekend or parties who are concerned about the exposure they might have had there," Dr. Pakes said.

Today, during his media briefing, Ontario Premier Doug Ford said the long lines at testing centres are "ridiculous." The premier announced the province would roll out a new plan regarding testing at pharmacies in the coming days, adding he needs to get his "ducks in a row."

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Parts of Ontario could see another lockdown, Premier Ford warned on Monday, if the province can't get the increasing rates of COVID-19 under control.

Ontario reports 251 new diagnoses on Tuesday and four new virus-related deaths.

Ford said the spike over the past two weeks is "cause for concern." The premier said if it comes to it, he would consider closing down the hardest-hit areas.

"We will take every step necessary, including further shutdowns," he said. "The second wave of COVID-19, it's a scenario that we've been preparing for all summer long."

Ford went on to blame partying and large groups for the surge in cases. "It's not the bars ... or the restaurants, it's social gatherings," he said. "So folks, I'm begging you. Please just cut out the social gatherings. It's just not worth it because this COVID is ramping up again."

With files from The Canadian Press