SALEM, Ore. (AP) - The head of Oregon's emergency management agency has apologized after a cryptic emergency alert was forced out to cellphones in and around Oregon's capital city, displaying the words "Civil Emergency" and "Prepare for Action," but carrying little other information.

Andrew Phelps said a technical glitch had cut off crucial information: that the alert concerned elevated levels of a natural toxin in a local reservoir. Children and people with compromised immune systems have been told not to drink tap water in the Salem, Oregon, area.

The incident marked a high-profile glitch in authorities' use of emergency alert systems. This comes after Hawaii officials sent out a false alarm out an incoming ballistic missile.

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