Relatives of the driver killed in a chase near the White House have told police that she had mental health issues, NBC News reports citing a senior law enforcement official.
Miriam Carey, 34, is said to have had a fall a couple of years ago leading to the issues.
Carey's employer corroborated that she had suffered a fall, and that she had returned to work pregnant.
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A man, reportedly armed with a knife and a baseball bat, was detained close to the event and police cleared the area as a precaution.
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