PORTLAND, Maine (AP) – Maine officials are urging more precaution in schools due to rising numbers of coronavirus cases in some parts of the state.

The administration of Democratic Gov. Janet Mills has been using a color-coded system to identify the level of risk of transmission of the virus at schools. Every county had been listed as green, the lowest-risk category, but the administration said Friday it is adding Androscoggin, Kennebec, Oxford and Somerset counties to the moderate “yellow” category.

The state is releasing the guidance as Maine’s number of daily positive coronavirus cases continues to trend upward.