Firefighters were called to a couple of fires at Hartford Public High School on Thursday morning.
Officials said the school dismissed early for the day after fires were found in two separate boys bathrooms.
Fire crews were called to the school just before 11 a.m. on Thursday for the report of smoke in the building.
The fires were found in two boys bathrooms, which were located on separate floors.
Police said garbage and paper were burned in each bathroom.
Students were dismissed early due to smokey conditions.
"This matter will be followed up by security and support staff, and with HPS's partnering community agencies," said Pedro Zayas, a spokesperson for Hartford Public Schools.
On Thursday afternoon, police said a student was identified as a suspect. That student was detained and was questioned by police.
No injuries were reported.
Zayas said the school will run on schedule Friday.