Iraqi paramilitary units said Wednesday they held the US responsible for a string of mysterious blasts in recent weeks at their bases, renewing fears of a possible proxy war. Over the past month, alleged attacks have targeted four training camps and arms depots used by the Hashed al-Shaabi, a network of mostly-Shiite, pro-Iran paramilitary units opposed to the US. On Wednesday, the paramilitary group said in a statement it had carried out its own investigation and pointed the finger at the US military, but also accused Israel of infringing Iraqi airspace.