TORONTO -- An Amazon warehouse that was ordered to shut down last week due to a major COVID-19 outbreak is also being investigated for potential labour violations, the Ontario government said Monday.

A spokesman for the Ministry of Labour said the investigation was already underway when the local public health unit ordered thousands of workers at the Brampton, Ont., facility on Friday to isolate for two weeks,

"We continue to work closely with Peel Public Health and others to provide support, advice and enforcement as needed to ensure the health and safety of Ontario's workers," Harry Godfrey said in a statement.

Godfrey noted that penalties for labour violations could be as high as $1.5 million or imprisonment. He said the government would not hesitate to hold employers accountable if they fail to keep their employees safe.

Peel Region's top doctor said the outbreak at the Amazon facility, which employs approximately 5,000 workers, began in October and has since been linked to more than 600 cases.

Dr. Lawrence Loh said nearly half of the cases were detected in the last few weeks, prompting the public health unit to issue a special order requiring the workers to self-isolate for two weeks starting March 13.

Workers were ordered to isolate until March 27 unless they've tested positive for COVID-19 in the last 90 days and have already completed their isolation period for that infection.

Amazon Canada said workers would be paid during the 14-day quarantine, but it disputed the data being used to support the plant closure, pointing to a round of tests that recently came back with a positivity rate of less than one per cent. It has said it plans to appeal the decision.

Peel Public Health said the closure will give the company further time to consider additional operational changes that may help prevent outbreaks in future.

The Ministry of Labour said its inspectors had visited the site 12 times and issued eight orders since March 2020.

Gagandeep Kaur, an organizer with Brampton-based Warehouse Workers Centre that advocates for workers' rights in the sector, said conditions had been getting worse in the facility for months. She said workers "were kind of surprised" that it took so long for public health to get involved and force the shutdown.

Kaur said people reported that safety precautions like physical distancing have been impossible to maintain inside, especially as workers rushed to meet strict productivity targets.

She said workers are now concerned that they will be asked to push themselves harder once they return from quarantine.

"They are not at home right now enjoying this two week vacation," Kaur said by phone. "They are more worried that once they are back ... management might put higher targets for them to reach."

Kaur said the pressures of the warehouse workplace, where employees' time on floor is constantly measured and tracked, created safety issues before the pandemic. Those challenges only increased with the viral threat that also coincided with more hiring, and greater demands as more people relied on the delivery service.

She said the company should use the two-week shutdown to implement changes at the plant such as further separating work stations and reducing performance targets as workers are dealing with the added stress of the pandemic.

"Amazon must use it wisely," she said of the shutdown. "Maybe implementing those changes inside the facility that will make the work safer so that we don't end up with this crisis again."

Last month, labour inspectors carried out a "blitz" operation on the warehouses and distribution centres in Peel Region - a COVID-19 hot spot with a high number of oubreaks in workplaces.

About 200 inspections took place and 26 tickets were issued, according the Ministry of Labour.

This report by The Canadian Press was first published March 15, 2021.