Blood on Klaus's shirt

As Václav Klaus was leaving the hospital on Fri., he pointed to the blood on his shirt and said to the reporters crowding around his Audi that they could see for themselves what had happened to him. Sure enough, there were three bloodstains on his white shirt. Anyone who has been shot by an overzealous son with an airsoft pistol must be wondering how the assailant could have drawn blood in three places through two layers of clothing, one of which was a men's suit. Bruises yes, but punctured skin and blood? FTV Prima quoted Jiří Šilhán of Airsoft Praha as saying that only a small bruise is possible through a suit. Of course the blood made Klaus's comments about an assassination attempt (slightly) more credible, but the presence of the stains raises serious questions. Are these pistols more dangerous than the manufacturers claim? Or is perhaps someone needlessly trying to stir up the people?