PFLUGERVILLE, Texas (AP) — A 25-minute cellphone video left behind by the bomber whose deadly explosives terrorized Austin for weeks details the differences among the weapons he built and amounts to a confession, police said. But his motive remains a mystery.

Mark Anthony Conditt, an unemployed college dropout who bought bomb-making materials at Home Depot, recorded the video hours before he died after detonating one of his own devices as SWAT teams closed in.

It seemed to indicate the 23-year-old knew he was about to be caught, said Austin Police Chief Brian Manley.

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