Authorities had zeroed in on the suspect in the last 24 to 36 hours and located him at a hotel on Interstate 35 in the Austin suburb of Round Rock, Austin Police Chief Brian Manley said at a news conference.

Police were waiting for ballistic vehicles to arrive when the suspect’s vehicle began to drive away, Manley said. Authorities followed the vehicle, which stopped in a ditch on the side of the road, the police chief said.

The suspect, who suffered significant injuries from the blast, was killed. Authorities identified him only as a 24-year-old white man.

Authorities said it was too soon to say if the suspect had worked alone in the bombings, which had killed two people and injured four others since they began March 2. They also said they don’t know the suspect’s motive.

Isaac Figueroa, 26, who lives near the scene on I-35, said he and his brother heard sirens and helicopters and drove toward them, then cut through nearby woods on foot after they hit a police roadblock.

Figueroa said the Jeep had been run into a ditch.

The suspect’s death followed a day of rapid-fire developments in the case.

On Tuesday, a bomb inside a package exploded around 1 a.m. as it passed along a conveyer belt at a FedEx shipping center in Schertz, northeast of San Antonio and about 60 miles southwest of Austin. One worker reported ringing in her ears and was treated at the scene.

Later in the morning, police sent a bomb squad to a FedEx facility outside the Austin airport to check on a suspicious package. Federal agencies and police later said that package had indeed contained an explosive that was successfully intercepted and that it, too, was tied to the other bombings.

The Schertz blast came two days after a bombing wounded two men Sunday night in a quiet Austin neighborhood about 3 miles from the FedEx store. It was triggered by a nearly invisible tripwire, suggesting a “higher level of sophistication” than agents saw in three package bombs previously left on doorsteps, according to Fred Milanowski, the agent in charge of the Houston division of the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives.

During an Oval Office meeting Tuesday, President Donald Trump said whoever is responsible for the bombings “is obviously a very sick individual or individuals” and that authorities are “working to get to the bottom of it.”

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