An Alaska charter school suspended three first-grade girls who had plotted to kill their classmate, according to their principal.

The three girls planned to use silica gel packets, which are commonly found in pre-packaged food products to keep moisture away, to poison another student, KTUU reported.

Three students in the class were planning on using the silica gel packets (These are not actually poison, but the students believed they were) from their lunchtime seaweed to poison and kill another student," Winterberry Charter School Principal Shanna Mall reportedly wrote in an email to parents on March 22.

Another student heard about the plan and told school administrators, said Jennifer Castro, spokeswoman for the Anchorage Police Department.

"We're grateful that that student was able to speak up and obviously at such a young age," Castro said. "The important lesson here is to really teach your kids if they hear something like this, something where someone intends to do harm to someone else, they should tell someone that they trust right away."

Administrators and school district psychologists talked to the girls to see if they understood what they were trying to do, whether it was a prank gone wrong or if they actually meant to hurt their classmate, school district spokeswoman Heidi Embley said.

"All of these things are being discussed, especially since it's such a young age," she said.

Police say the plot emerged from an ongoing feud but did not release any other details. Two other first-graders told school officials about the plan, and the officer also spoke with them.

The two students reported to administrators that the plan involved using the packets from the girls' "lunchtime seaweed to poison and kill another student," Principal Shanna Mall wrote in the email.

Police left discipline up to the school district. The email said it entailed "significant consequences."

Embley said she couldn't release further details about how the students were punished.

But Mall told Anchorage television station KTUU that the students were suspended. Mall couldn't immediately be reached for comment Wednesday by The Associated press.

Asked if the school was getting calls from concerned parents or hearing from worried students, Embley said there was "nothing significant."

The school is addressing any concerns directly with parents or students.

The Associated Press contributed to this report.

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