North Korea conducted a fifth ever nuclear test Friday morning, described by South Korea’s Joint Chiefs of Staff as the reclusive state’s “biggest-ever” with a yield reaching 10 kilotons. The amount is almost double what Pyongyang claimed was a hydrogen bomb earlier this year....

Evenings across the U.S. this summer were balmier than any other summer since records began in 1895, the National Oceanic and Atmospheric Administration (NOAA) said in a report Thursday. NOAA defines summer as the three-month period between June and August in which the average low...

The U.S.-led war on Islamic State has depleted the group's funds, leadership and foreign fighters, but the biggest battle yet is expected later this year in Iraq's northern city of Mosul, where Abu Bakr al-Baghdadi declared his "caliphate" two years ago. The jihadist insurgents have lost...

U.S. Secretary of State John Kerry flew into Geneva on Friday for a new round of talks with Russia on a Syrian ceasefire, with U.S. officials saying they believed a deal was still possible, but warning that the talks could not go on forever. Senior State Department officials briefing...