amber alert 72b381

An unofficial Amber Alert that apparently originated in Salt Lake City last Sunday night crisscrossed the country over the following two days, convincing well-meaning text messagers and Twitter users from Maryland to California that a 7-year-old girl in their state had been abducted by a man driving a "newer silver truck" with the license plate number 72B381.
The message is false. Police say there are no real missing-person cases fitting that description.
A very early version of the alert read as follows:
FWD: FWD: FW: AMBER ALERT A 7 yr old girl was taken by a man driving a newer silver truck. The license plate reads 72b381 please please pass on.
By the time Utah authorities disavowed the bogus message on Monday, it had already spread to Wisconsin...
Retweet: AMBER ALERT. A seven year old girl was taken by a man driving a newer silver truck. license plate # 72B381 Menomonie area FWD PLZ
...not to mention Woodward, Oklahoma...