TORONTO -- New public health measures meant to limit the spread of COVID-19 went into effect across nine Ontario regions today, including two that are heading into lockdown due to rising case counts.

The Thunder Bay and Simcoe-Muskoka health units have seen infections rising in recent days, driven in part by transmission of more infectious variants of the virus.

The province activated what it describes as an "emergency break" for those districts, moving them to the grey tier of Ontario's colour-coded pandemic response plan.

The move will impose a variety of more stringent public health measures in those regions, including capping most indoor gatherings at 10 people, closing restaurants to in-person service and forcing non-essential retailers to operate at 25-per-cent capacity.

Seven other public health units will be easing restrictions as they move down a level in the provincial framework.

The Niagara Region is now classified as red, the Chatham-Kent, Middlesex-London and Southwestern units all move to the orange tier, Haldimand-Norfolk and Huron Perth transition to the yellow level, and Grey Bruce will become a green zone with the least restrictive measures in place.

This report by The Canadian Press was first published March 1, 2021.