Fourteen Queensland children are in hospital after they became sick from eating an unknown substance on a school bus in Townsville.

Fourteen children have been rushed to hospital after eating an "unknown substance" which was reportedly in lollies handed out on a school bus in north Queensland.

Paramedics took the children to hospital to be treated for "minor illness symptoms" after being called to Bluewater State School in Townsville on Thursday.

"Six patients transported to Townsville Hospital in stable conditions for minor illness symptoms after they reportedly ingested an unknown substance in Bluewater," the Queensland Ambulance Service said on Twitter.

"A further 8 patients were transported to Townsville Hospital in stable conditions after an incident at Bluewater."

Bluewater State School said police are investigating the incident, but it could not provide further details due to "privacy issues".

"Bluewater State School holds the safety of students and staff as its highest priority," it said in a statement posted on Facebook.

"The department is aware of an incident that occurred today at Bluewater State School which required the assistance of emergency services.

"School staff acted quickly to attend to the students while the Queensland Ambulance Service and parents were contacted."

The school said guidance counselling would be offered for any children involved.

AAP