(CNN) — Twelve elementary school children drank floor sealant believing it was milk after it was served to students at a childcare program in Juneau, Alaska, on Tuesday, according to the school district.

Students in a summer care program at Sitʼ Eeti Shaanáx̱-Glacier Valley Elementary School began complaining that the milk they were served as part of the program’s breakfast tasted bad and was burning their mouths and throats, Juneau School District said in a statement Wednesday.

The breakfast was served onto trays by an outside contractor, NANA Management Services, at about 8:45 a.m. on Tuesday and the children brought their trays to a cafeteria table to eat, the district statement said.

After the children complained about the burning sensation, school district and NANA staff “immediately followed up by smelling/tasting the milk and looking at the container/label,” the statement said. “It was found that the ‘milk’ served was actually a floor sealant resembling liquid milk. Staff immediately directed students to stop consuming the substance and removed it.”

The site manager for RALLY, the summer care program, contacted poison control and alerted parents, according to the statement, and “all steps provided by poison control were carefully followed.”

RALLY provides state-licensed childcare for elementary students ages five through 12 and is a partnership with the Juneau School District, according to the district website.

One student received medical treatment at a nearby hospital, and two other students were picked up from the school “and may have gone to seek medical advice,” the statement said.

The condition of those students and the remaining nine children was not included in the statement.

An investigation into how the incident happened is ongoing and includes participation from the school district, NMS, the City and Borough of Juneau, and Juneau Police Department, according to the statement, which did not specify who is leading the investigation.

CNN has reached out to the Juneau School District, NMS and the Juneau Police Department for more information.

(Copyright (c) 2022 CNN. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

Join our Newsletter for the latest news right to your inbox