A misunderstood text message triggered a precautionary lockdown at South Plainfield High School Friday, but police at the scene determined that no threat existed.

School Superintendent Dr. Stephen Genco told New Jersey 101.5 that a "misinterpreted text message from a daughter to a mother" drew the police response and put established emergency measures into play at the high school as well as South Plainfield Middle School and the Grant School, which share the same campus.

A full explanation was later posted on the school district website. Here is the text:

"We have just received confirmation from the police that the Middle School, Grant School and the High School are no longer in lockdown. As you know, today there was an incident that caused authorities to put the HS , Middle School and Grant into a lockdown situation. The police have concluded their investigation and have determined that there was no threat. Currently the police are concluding their procedures and have authorized the reopening of all three buildings. All procedures were followed and it was clear that the practice drills we hold in each of our schools assisted in readying the students and staff for this incident. Thank you for your patience and support."

New Jersey 101.5 had received several calls from parents, inquiring about the nature of the incident before lockdown was lifted.

Several police units had converged on the schools and a "shelter in place" order was issued, confining students to their classrooms until a full sweep of the facilities was completed. K9 dogs were part of that search, according to ABC 7.

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