ROYAL OAK, Mich. (CBS DETROIT) –  A 33-year-old Royal Oak man was faces felony charges after sending bomb threats through emails within a 90-minute time span last week.

Police said Adam Laird has no criminal convictions, nor do they have a motive for threats.

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He’s been charged with eight counts of a felony charge of threat of terrorism and another count of malicious use of telecommunications services.

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Laird was arraigned Sunday and ordered held in lieu of $500,000 bail.

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