PARIS (AP) — With more asthmatic children needing hospital treatment in Paris amid exceptional air pollution, France's government put medics on alert Friday and warned residents to limit outdoor activity over the weekend.

The Paris public hospital authority reported that it had 2,045 emergency visits by asthmatic children during the first week of December, compared with 1,516 in the same period last year.

The hospital authority remained cautious in a statement about singling out a cause, but noted the health threats from the kind of particulate matter pollution currently blanketing Paris.

Health Minister Marisol Touraine said Friday that hospitals were on alert for emergency respiratory problems across the Paris region and in southeastern France.

Meanwhile, the Paris police chief decided to allow cars to circulate again without restrictions in the French capital starting Saturday.

An alternating traffic ban on cars based on odd or even-numbered license plates has been in effect for four consecutive days, a first in Paris.

The pollution is expected to diminish slightly over the weekend.