MONTREAL -- Quebec public health authorities say they are seeing a worrying spike in infections among teens and young adults.

Deputy premier Genevieve Guilbault told a news conference Monday a significant portion of the daily COVID-19 cases in the province involve people between the ages of 15-34.

Guilbault says despite the fact the COVID-19 situation in Quebec remains under control, young people need to recognize they are not immune from health complications tied to the novel coronavirus.

The minister also says she was shocked to see images of anti-mask protests in Montreal and Quebec City over the weekend, during which protesters accosted journalists and failed to follow health directives.

She says authorities will crack down on protesters who put the health of others at risk.

Health officials Monday reported 145 additional cases of COVID-19 since Sunday, bringing the total to 58,728. There were no new deaths reported.

Quebec has had a total of 5,667 COVID-19-related deaths since the beginning of the pandemic. There are 200 people in hospital with the disease, including seven in intensive care.

Guilbault said Monday that even if most young people are less likely to suffer seriously from the disease, "they can be vectors of transmission to more vulnerable people, such as their parents or grandparents."

Commenting on the protests against mandatory masks, she said people have the right to demonstrate against the government. However she added that she was "particularly shocked to see protesters insulting and physically intimidating journalists -- that is not acceptable."

Meanwhile, Quebecers using public transit can now be denied service for not wearing a face-covering as a two-week grace period came to an end Monday.

But some transit agencies in the Montreal area say they'll continue to count on awareness campaigns and handing out masks to ensure compliance.

In an effort to slow the spread of COVID-19, Quebec has made masks mandatory since July 13 for anyone riding on public transit, except for those who can't wear one for health reasons. Quebec has also made masks mandatory in indoor public places since July 18.

This report by The Canadian Press was first published July 27, 2020.