The number of vehicles clogging up the roads in Paris was sharply reduced on Monday due to anti-pollution measures, according to the authorities.<br /><br /> The reason for the latest restrictions banning half of all traffic in the capital was a nasty smog affecting urban areas across northern France.<br /><br /> Police in Paris were out to enforce the rules authorising only vehicles with licence plates ending in odd numbers.<br /><br /> Similar restrictions were imposed a year ago.<br /><br /> The police reported that morning rush-hour traffic jams were down by a third, and Paris mayor Anne Hidalgo said that the number of cars on the roads at 9am was 40 percent less than usual.<br /><br /> #Pollution : à cette heure, il y a environ 40% de moins de circulation dans #Paris— Anne Hidalgo (@Anne_Hidalgo) March 23, 2015<br /> <br /><br /> Thousands of motorists who defied the restriction were given on-the-spot fines of 22 euros. <br /><br /> One visitor from outside Paris supported the ban: “It’s a good thing firstly for traffic: it’s much nicer to drive in Pari