TYNGSBORO -- The two cars that had "positive hits" for possible traces of narcotics Thursday morning at Tyngsboro High School were cleared in the afternoon, according to police.
Police Chief Richard Howe said he was notified by his school resource officer that the vehicles with positive hits by the K-9s were searched. No evidence or illegal substances were found and Howe said that would be the end of their investigation.
"It could have been residue," he added. "It could have been a false positive."
A positive hit means traces of narcotics from the past or present were detected, but "we don't know and we're looking into it," Howe said earlier, before the investigation was done.
The school went into a soft lockdown during the 45-minute planned drug sweep at around 9 a.m., according to Howe.
"There was no active incident," he said. "It's part of the ongoing activity with the school, where we do a periodic drug sweep. Students remained in class the whole time."
Samantha Allen contributed to this report.
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