In Iraq, twin car bombings on Sunday in both Baghdad and Tikrit killed 25 and wounded at least 100 in one of the bloodiest days since the January elections. The deadliest attack occurred outside a Shiite mosque in Baghdad. There a vehicle packed with explosives drove into a crowd near the mosque. Then as police and residents rushed to help the victims — another suicide car bomber drove into the crowd. On Saturday, 16 people died including a cameraman working in Mosul for the Associated Press. U.S. officials are now saying the number of bombings and attacks by the Iraqi resistance has increased by as much as 40 percent since the end of March.