Pfizer has begun a study comparing its original COVID-19 vaccine with doses specially tweaked to match the hugely contagious omicron variant. Pfizer and its partner BioNTech announced the study on Tuesday. COVID-19 vaccine makers have been updating their shots to better match omicron in...

Clashes between U.S.-backed Syrian Kurdish fighters and militants continued for a fourth day Sunday near a prison in northeastern Syria that houses thousands of members of the Islamic State group, the Kurdish force said. The standoff follows a bold assault by the extremists that breached the...

MOSCOW (AP) — Russia’s Foreign Ministry on Sunday rejected a British claim that the Kremlin is seeking to replace Ukraine’s government with a pro-Moscow administration, and that former Ukrainian lawmaker Yevheniy Murayev is a potential candidate. Britain’s Foreign Office on Saturday...

A group of migrants huddles beside a small, smoky fire inside an abandoned building in northern Serbia, the last moments of warmth before they set out into the driving snow toward the razor wire, cameras and sensors of Hungary's electrified border fence. A few hours later, they return, their...