At least one attacker opened fire on Dallas’ police headquarters early Saturday, riddling windows and police cars before fleeing in a van to a suburban restaurant parking lot, where officers surrounded the vehicle in a standoff that has lasted for hours

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Officers exchanged gunfire with the attacker or attackers at both sites, and as dawn broke in Texas – hours after the near-midnight attack began – they still were watching the vehicle and negotiating with the driver in the parking lot of a Jack in the Box restaurant in Hutchins.