BERLIN (AP).- An Afghan boy on a swing ride with a toy submachine gun in his hand. A black-clad Iraqi mother giving a bottle to her baby daughter outside Abu Ghraib prison as she waits for the release of detainees. A U.S. Marine mourning the loss of 31 comrades in Iraq. The powerful images are among some 40 black-and-white photographs by Associated Press photographer Anja Niedringhaus from conflict zones around the world presented to journalists Friday at the Berlin gallery C/O Berlin. The exhibition “At War,” co-sponsored by The Associated Press and the Deutsche Boerse Group, runs in the German capital from Saturday through Dec. 10 before moving in early 2012 to the Deutsche Boerse headquarters in Eschborn, near Frankfurt. Niedringhaus, 45, took the pictures during tours in Kuwait, Iraq, Afghanistan, Libya, Gaza and the West Bank during a 20-year stretch covering war