By Agence France-Presse
A series of blasts that has killed two people and injured several others has left the Texas state capital of Austin on edge.
Authorities responded late Tuesday en masse to the scene of another reported explosion, which turned out to be unrelated to the previous cases and caused by an "incendiary device," not an explosive package, according to Austin police.
In the early morning hours, a package exploded at a FedEx facility in Schertz, outside of San Antonio and approximately 65 miles (105 kilometers) south of Austin.
Officials connected that blast to four other bombings since early March, which killed two people and injured several more.
There were no serious injuries in the incident that saw a package at a FedEx sorting facility detonate.
"It was mailed from Austin, it was to an Austin resident and it blew up on the conveyor belt," state attorney general Ken Paxton told KXAN television.
US Congressman Michael McCaul, the head of the House Homeland Security Committee who said he had spoken to law enforcement, added: "All these devices are very similar."
Law enforcement confirmed they had found another package connected to the bombings at a separate FedEx facility near the Austin airport.
That package was discovered early in the day.
FedEx said it "secured and turned over to law enforcement" the second package, sent by "the individual responsible" for the blasts.
The company said in a statement that it had also provided "extensive evidence related to these packages and the individual that shipped them collected from our advanced technology security systems."
The finding could be significant to investigators looking for evidence in their efforts to identify the perpetrator or a motive.
As the series of bombings held Austin on edge for another week, the White House weighed in for the first time since the crime wave began.
"The bombings in Austin are terrible. Local, state and federal law enforcement working hand in hand to get to the bottom of it," Trump said.
"This is obviously a very, very sick individual or maybe individuals. These are sick people, and we will get to the bottom of it."
- 'Absolutely no clue' -
Despite hundreds of police officers and federal agents working the case, authorities appeared to have few leads.
"We have no clue who this is, absolutely no clue," Texas Congressman Brian Babin told the Fox Business Network.
"I'm sure the FBI and the law enforcement agencies that are looking into this have some tips, some clues, but I haven't heard anything about it."
Senator Ted Cruz said he had spoken to Austin's mayor and police chief about the "coordinated attacks," saying no effort should be spared to catch the bomber and "put him behind bars before anyone else's life is at risk."
"It's truly horrific what is happening in Austin," Cruz told reporters in Washington.
Austin's police chief Brian Manley said the bombings seemed to be evolving.
The first three explosive devices were concealed in packages left at residents' doorsteps. A fourth was detonated with a tripwire, which Manley said suggested a perpetrator who "shows a higher level of sophistication, a higher level of skill" than initially believed.
"And with what just occurred in Schertz, Texas, we've now brought in a new element that that device was actually going through one of the carrier services, instead of being hand-delivered," Manley told an Austin city council hearing.
More than 1,200 calls have come in from residents since police urged them to report suspicious activities and items, Austin police said.
"I will reach out to the suspect or suspects and ask that you contact us... communicate with us so that we can put this to an end," Manley said.
Authorities increased the reward offered for information leading to an arrest, bringing the total bounty to $115,000.