ROUGH CUT (NO REPORTER NARRATION)<br/> <br />At least five people were killed and more than 100 hurt in an explosion at a security building in Egypt's Nile Delta town of Dakahlyia on Tuesday, state media and a security source said.<br/> <br />A security source said the cause of the explosion was unclear, but that the force of the blast had led to the collapse of parts of the security building.<br/> <br />Another security source said the blast may have been caused by a car bomb, but it was not yet clear if it was suicide attack or not.<br/> <br />State TV said five people were killed and more than 100 hurt. It said two top security officials were among the injured.<br/> <br />Egypt's Nile News TV cut into its late-night programming to urge people to go to hospitals to donate blood to the victims of the attack, which it described as the worst in the city's history.
