Connecticut Attorney General William Tong announced late Monday that his office is in the process of joining with other states investigating Hyundai USA and Kia Motors America for potential unfair and deceptive practices related to spontaneous vehicle fires.

“My office is one of the leaders of an ongoing multistate investigation into deeply troubling reports of spontaneous fires in Hyundai and Kia vehicles,” Tong said in a statement. “We are aware of multiple fires involving Connecticut vehicles, including some allegedly already repaired through the recall process. This is a serious matter, and we are moving aggressively and responsibly to uncover the facts and to ensure accountability.”

Elizabeth Benton, spokeswoman for the Office of the Attorney General, told the Connecticut Law Tribune Monday that the office is limited on what it could release to the public because “there is an ongoing investigation at its early stages.” Benton could not say how many other states have or would  sign on to the investigation.

According to Tong's office, cars have caught fire while in use or parked on the street or in garages. Some consumers, the release said, reported that their car hesitated or stalled and that the check-engine light illuminated moments before they saw smoke coming from the engine compartment.

Both automobile manufacturers initiated recalls of several hundred thousand cars equipped with the Theta II Gasoline Direct Injection engine beginning in 2015.

Representatives from Hyundai and Kia's press offices did not immediately respond to a request for comment late Monday.

This is a developing report, and will be updated.