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AUSTIN, TX (CBSMiami) – The Mayor of Austin and the city’s police chief are warning residents not to open any suspicious packages.

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This after two exploded Monday morning, killing a 17-year-old male and injuring two women.

The second package exploded around noon. Officials say a woman in her 70s was taken to a local medical center with serious, potentially life-threatening injuries. A woman in her 80s was evaluated at the scene but was not taken to the hospital.

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The first happened in Central East Austin at a home where a suspicious package was left on the doorstep of a single-family residence. A 17-year-old boy was killed, and a woman in her 40s was injured.

Police are investigating whether the explosion is linked to another deadly home explosion on March 2nd when a man was killed. Police are investigating both cases as homicides.

Investigators searching for a motive for the crimes say they cannot rule out the possibility of both instances being hate related. Both homes where the packages were delivered belonged to African Americans.

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Police Chief Brian Manley said it does not appear the packages were mailed but were instead delivered to the front doorstep in both cases.