UPDATED: March 12, 2018  11:45 AM

AUSTIN (CBSDFW.COM/AP) – Authorities say a package that exploded inside of an Austin home on Monday, killing a teenager and wounding a woman, is believed to be linked to a deadly package sent to another home in Texas’ capital city earlier this month.

NEW – Austin Police Respond To Second Reported Explosion Today

Austin police Chief Brian Manley said at a news conference that investigators believe the attacks are linked because in each case, the package bombs were left on the victims’ front doorsteps and not delivered by a mail service. He said the U.S. Postal Service doesn’t have a record of delivering a package to the Austin home where the explosion occurred Monday.

“Early this morning one of the residents went out front, and there was a package on the front doorstep,” said Manley. “They brought that package inside the residence and as they opened that package — both victims were in the kitchen — and the package exploded,” he said.

Manley said investigators believe the explosion is linked to a similar blast that killed a 39-year-old man on March 2. That explosion occurred about 12 miles north of Monday’s blast. Both explosions occurred in the early-morning hours.

Until the cases are cleared Chief Manley had a message for residents. “If you’ve received a package that you are not expecting that is not from someone that you expected to receive a package from, or for some reason gives you case for concern, then call 911.”

In the March 2 explosion, Chief Manley told the paper that authorities received several calls reporting the incident. The man died at the hospital from his injuries.

Police were investigating that incident as a suspicious death, but have now been reclassified the case and are investigating it as a homicide.

Investigators don’t yet know the motive behind the bombings but the Chief said, “We do know that both of the homes that were the recipients of these packages belonged to African Americans, so we cannot rule out that Hate Crime is at the core of this, but we’re not saying that that’s the cause.”

Police said they do know what type of explosive device was used in each explosion but aren’t releasing that information “to protect integrity of investigation.” There have been no possible suspects named in either case.

The FBI, ATF and U.S. Postal Service are all helping Austin police in the investigation.

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