Local police, as well as agencies including the FBI, and the Bureau of Alcohol, Tobacco, Firearms and Explosives, are working on the case.
The woman injured by the blast was rushed to the hospital where she is being treated for serious injuries. The package was brought inside and as it was opened, it exploded in the kitchen resulting in the injuries.
Police said the package was not delivered through the US Postal Service and suggested that it did not come through any other package delivery service.
Both cases are now being investigated as homicides, Austin Police Chief Brian Manley said during a news conference Monday.
The package detonated early Monday.
Like the March 2 explosion, Manley said there was no immediate indication of terrorism in Monday's incident, but added that police were looking to see if there was a "specific ideology behind these offenses" or if there was the possibility of a hate crime as victims in both cases were African American.
Original report: A teenager was killed and a woman was injured early Monday in East Austin after a second package exploded in the city in the past two weeks, authorities said.
Officials are now warning the community to be aware of suspicious packages found. Police say to not handle any suspicious package found on a front porch, but to instead call 911 so they can inspect it.
Police warned the public about handling packages they are not expecting.
Investigators are trying to determine whether the explosion is linked to a similar blast that killed a 39-year-old man on March 2. Police say the woman is in her 40s, but they haven't released any other information.
The latest explosion occurred about five miles from the Austin Convention Center, the site of South by Southwest activities on Monday.