(Al Jazeera English News Headlines: June 23, 2010) U.S. president Barack Obama has fired his head commander in Afghanistan, Gen. Stanley McChrystal, in the fallout of a Rolling Stone article where McChrystal and his staff were openly critical of the Obama administration. BP has hit another snag in its attempt to control the Gulf oil spill, as an underwater robot collided with the containment cap, causing more oil to gush into the Gulf of Mexico. Rescue efforts continue in Brazil, where hundreds are missing after devastating floods. Ethnic Uzbek refugees have begun returning home to Kyrgyzstan after ethnic violence forced them to flee to neighboring Uzbekistan.