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Chinese man wears a protective face mask as he passes by the CCTV building on a day of heavy pollution on Monday in Beijing, China. China’s capital and many cities in the northern part of the country recorded the worst smog of the year with air quality devices in some areas unable to read such high levels of pollutants
Helpers hold a balloon of the developmental advocacy and campaigning organisation ‘ONE’ depicting US President Barack Obama while it is filled with air on the Odeonsplatz in Munich on Friday
A member of the Patrouille Suisse flight team of the Swiss Air Force performs in his Northrop F-5 ll Tiger fighting jet during a media day of the Swiss Air Force at the airbase in the central Swiss town of Emmen on Friday
A Greek Army Apache helicopter takes part in an air show at Athens Paleo Faliro coastal suburb on Thursday
Hot air balloons lift off during a mass ascent at the 36th International Balloon Fiesta at the Ashton Court Estate near Bristol, which is Europe’s largest ballooning event which officially begins on Friday
Tourists from mainland China take photos in front of a large outdoor banner showing what Hong Kong looks like on a clean air day, on Wednesday. Hong Kong’s air pollution index’ reached ‘very high’ in Central and Western District, Causeway Bay and Mongkok, with ‘very high’ levels of toxic ozone and nitrogen dioxide recorded at roadside monitoring stations
A boy watches Israeli Air Force CH-53 helicopters fly over the Mediterranean Sea on a Tel Aviv beach during an aerial show forming part of celebrations for Israel’s Independence Day on April 16 2013, marking the 65th anniversary of the creation of the state.