Multiple gunmen inside a van opened fire Saturday on downtown Dallas police headquarters, leaving bags filled with pipe bombs and ramming a police vehicle as they drove off. No officers were injured in the attack. The police gave chase and disabled the vehicle with 50-caliber rifles. Negotiations are ongoing to discover the identities of the gunmen and the motive behind their attack. One occupant of the van was said to have identified himself as James Boulware. Officers said they had attended three incidents of domestic violence involving a man of that name who he said he wanted to blow up the police because they had taken his child and accused him of being a terrorist.