At least 18 killed by tornadoes in Arkansas, Oklahoma and Iowa
USA-TORNADO/WEATHER (PIX, TV, UPDATE 1):UPDATE 1-At least 18 killed by tornadoes in Arkansas, Oklahoma and Iowa
Natural gas-gobbling bacteria may help combat oil leaks
ENVIRONMENT-BACTERIA/:Natural gas-gobbling bacteria may help combat oil leaks
Indigenous anti-dam activist in Peru wins top U.S. environmental prize
Recipient Ruth Buendia is a 37-year-old leader of the Ashaninka people in the Peru's central Amazon
A woman walks with her greyhound dogs along a path in the Durand forest near the French border to Switzerland in Ferney Voltaire
A woman walks with her greyhound dogs along a path in the Durand forest near the French border to Switzerland, in Ferney Voltaire April 28, 2014. REUTERS/Denis Balibouse (FRANCE)
French energy minister promises 100,000 green jobs
FRANCE-ECOLOGY/EMPLOYMENT:French energy minister promises 100,000 green jobs
A man harvest qat leaves in his farm on the outskirts of Sana'a
A man harvest qat leaves in his farm on the outskirts of Sana'a, April 25, 2014. Many of Yemen's 25 million people chew qat leaves for their mild stimulant effect. REUTERS/Mohamed al-Sayaghi (YEMEN - Tags: AGRICULTURE DRUGS SOCIETY ENVIRONMENT)
Storms blowing in tornado threat across U.S. Plains this weekend
USA-WEATHER/:Storms blowing in tornado threat across U.S. Plains this weekend
French Ecology, Sustainable Development and Energy Minister Segolene Royal attends a news conference in Paris
French Ecology, Sustainable Development and Energy Minister Segolene Royal attends a news conference in Paris, April 25, 2014. REUTERS/Christian Hartmann (FRANCE - Tags: POLITICS ENVIRONMENT TPX IMAGES OF THE DAY)
French Ecology, Sustainable Development and Energy Minister Segolene Royal attends a news conference in Paris
French Ecology, Sustainable Development and Energy Minister Segolene Royal attends a news conference in Paris, April 25, 2014. REUTERS/Christian Hartmann (FRANCE - Tags: POLITICS ENVIRONMENT)