Street view as Bullets Go offA police source has confirmed that someone in an armored van fired shots at Dallas police headquarters early Saturday, prompting a pursuit involving dozens of police vehicles.The gunman has been corneredin the van along Interstate 45 near Hutchins after more shots were fired at that location. Police were concerned about the possibility the vehicle might be carrying explosives.Video footage of the scene near the headquarters confirmed that at least one police vehicle hadbeen struck, but Maj. Max Geron said no injuries had been reported. It appeared at least one window had been shot out of the building.People began reporting shortly before 12:30 a.m. that a gunman had fired into Jack Evans Police Headquarters on Lamar Street, south of downtown. Officers were patrolling the area to ensure there were no other dangers.Dallas police announced about 2:15 a.m. that they were implementing extra precautions at other police facilities.SWAT personnel were reported to be working to arrest the gunman as southbound I-45 near Dowdy Ferry Road was shut down. People were being ordered to stay away from the area, and police were prepared for the possibility that the van might be carrying explosives.The van had a Georgia license plate, but no details about the gunman were available yet.Alexis Trejo said he was parked behind a McDonald's on the other side of I-45 about 12:45 am when he heard helicopters overhead."I didn't think much until we saw lights, then we just hear a bunch of gunshots," he said.Other people gathered in the parking lot of the McDonald's said they heard gunshots just before police shut down the highway.