LAFAYETTE, Colo. – Boulder County sheriff’s deputies say a man and a woman were seriously injured after a package left at their home exploded Saturday afternoon.

Their conditions were not immediately known, The Denver Post reported.

Police say they believe there may be another package in the car and were searching it with a bomb robot.

Neighbor Tim Walker told the Post that the woman had picked up two packages left at her doorstep and was loading them into a silver Volvo, parked outside the home, when one blast occurred.

Deputies evacuated several residences from the neighborhood by using ladders to help people climb over fences, the Denver newspaper reported.

Msnbc.com staff and The Associated Press contributed to this report.

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