Sitʼ Eeti Shaanáx̱-Glacier Valley Elementary School
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 on trays by an outside contractor, NANA Management Services (NMS), 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 NMS 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 5 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.

In a separate statement sent Thursday, NMS said it dispatched its safety team to Juneau as soon as it became aware of the incident, “and leadership are en route to Juneau now.”

“We are supporting the full investigation, looking at every contributing factor to determine exactly what happened. This process is key to identifying potential safety measures and putting those safety measures to work,” the NMS statement reads.

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

CNN’s Elizabeth Wolfe contributed to this report.