A tire vandalism spree on Portland's east side now has hundreds of victims, but police have not identified any suspects.
Fox 12 first reported on the rash of punctured tires this summer.
Police have now received 539 reports, totaling $300,000 in damage.
The reports stretch across three police precincts in northeast and southeast Portland.
The tires are usually punctured overnight and victims typically notice a slow leak in a tire. Many victims have been hit more than once.
The Richmond Neighborhood Association and the Hosford-Abernethy Neighborhood District Association sent a letter to the mayor and police chief, asking for more to be done in the investigation.
A spokesman for the Portland Police Bureau said investigators have devoted many resources to the case, including some investigative measures they do not want to reveal.
But with no witnesses or suspect description, and with very little evidence, the case is proving tough to solve.
Police recommend vehicle owners keep an eye out for suspicious activity.
Crimestoppers is offering a cash reward of up to $1,000 for information that leads to an arrest in this case.
Leave a Crime Stoppers tip online at http://crimestoppersoforegon.com/submit_online_tip.php text CRIMES (274637) and in the subject line put 823HELP, followed by your tip, or call 503-823-HELP (4357) and leave your tip information.
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