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CORINTH (CBSDFW.COM) – Corinth Police and the Lake Dallas Independent School District say the district’s computer system was hacked by students.   They say it might have occurred in the spring of 2014, but not discovered until December.

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At first they thought it was just an in-school prank to get homework help involving 12 to 13 students and Lake Dallas High School. But now it’s mushroomed into a second investigation with four new complaints, a felony identity theft probe of lunch money stolen electronically.

“Yeah, I’m a little concerned, I think everybody is,” said Robert Dees, who has a 16-year-old daughter at the school. He says his daughter and her friends worry their lunch accounts may have been hacked.

“I know all the kids talk about it and they’re concerned about their pre-paid lunch money being deleted out of their account,” Dees told CBS 11.

Police say the original breach occurred in an unprotected file on a school computer the students were authorized to use. It was downloaded to a thumb drive and passed around to 12 to 13 students. “And that, of course, allowed them to gain access to over 3,000 names, addresses, personal identifiers, dates of birth, social security numbers,” said Assistant Corinth Police Chief Greg Wilkerson. The school is located in the city of Corinth.

The district tells CBS 11 it thought the original breach pertained only to homework, that its private probe disciplined the students involved, and that all offending data had been destroyed. Last month it even sent out a letter telling parents no personal information had been misused. Sadly, that wasn’t accurate according to Wilkerson.

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“They (ISD investigators) did not reach out or file any criminal reports of ask us for any help at that time. Now that the information has been put out to the public we believe there have been some criminal offenses.”

It was parents themselves who alerted police about missing money beginning last Friday. Four complaints so far triggering a criminal probe. And the district having destroyed the original breached data makes investigators’ jobs much harder. “It does change the way we operate, it changes the way we have to investigate this now; they’re privy to a lot of information that we’re not.”

No one from the school district would talk on camera but a spokesperson did answer questions over the phone and said the 12 to 13 students in the original data breach are minors.

Police say they don’t know how much money may be involved or how the probe will go, but those 12 to 13 students will certainly be the starting point.

(©2015 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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