Dallas Police Headquarters Shooting: A Timeline

— -- Authorities in Dallas are investigating an attack against police early this morning that left the gunman dead.

The suspect has not been identified, but police confirmed this afternoon that the suspect was dead in his armored van.

Police said they cannot confirm the suspect's motive.

Here is a step-by-step look at Saturday's events (CDT):

12:30 a.m.:

Around 12:30 a.m., a gunman opened fire from a parked, armored van in front of Dallas' Jack Evans Police Headquarters.

"Witnesses observed what they believed to be multiple suspects firing gun shots," Dallas police said, but police said they believed it was a lone shooter firing from various locations.

The suspect rammed a police squad car and fired shots at the squad car, police said.

Officers returned fire and the suspect fled.

12:45 a.m.:

At about 12:45 a.m., officers chased the suspect to a fast food restaurant parking lot in Hutchins, Texas, about 13 miles away from the department's headquarters, police said, where gunfire was exchanged.

No officers were injured in the shootings.

4:30 a.m.:

Police found a bag containing pipe bombs near police department headquarters. When a robot picked the bag up, it detonated.

5:00 a.m.:

A police sniper shot at the suspect through the front windshield of his van.

The suspect may have been hit and may have been killed, police said.

5:40 a.m.:

Police completed planned detonations at headquarters. Within the hour, all packages at headquarters were cleared.

11:30 a.m.:

All police substations were cleared.

12 p.m.:

At least two more pipe bombs were found inside the suspect's van, police said.

1 p.m.:

Police said the suspect in the van is dead. The gunman's identity was not confirmed.

This story is developing.