Darien Police Lt. Jeremiah Marron said a message was found on a bathroom wall that said, "gonna shoot the school per. 6. B ready."
The discovery of the message sent the school into a lockdown Friday afternoon.
"We were there already for a fire alarm so we were in place for it," Marron said.
He said precaution was necessary as Period 6 was upcoming. However, after an investigation, police determined the threat was unfounded and the lockdown was lifted after 22 minutes, he said.
On Wednesday, several students reported reading a message in a bathroom that said "Do not come to school on 3/23." Police investigated, but didn't find anything and declared the school safe.
Marron said police are determined to find out the suspect or suspects who are in making the threats.
In a message to the school community, Superintendent of Schools Daniel Brenner said the district takes school safety seriously.
Brenner also dispelled a rumor that there was a gun at the school Friday.
"This is absolutely false," he said in the message. "Please be assured that these incidents have been found to have no substance and that there was no threat present at any time."
Brenner said Friday's event may have been "copycat" behavior.
"While this appears to be the case today, we will always take each case seriously and act accordingly," Brenner said.
The district will continue its investigation in collaboration with Darien Police to identify who was responsible, he said.
"I can assure you that once identified, we will discipline the individual(s) to the full extent of education and criminal law," Brenner said.
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