Washington: The top US auto safety regulator said on Monday it will open an investigation into 3 million Hyundai Motor Co and Kia Motors Corp vehicles after reviewing reports of more than 3000 fires that injured over 100 people.

Hyundai is under investigation after its vehicles were involved in a number of fires. Credit:Bloomberg

The National Highway Traffic Safety Administration said the investigation is in response to a petition seeking a probe filed last June by the Centre for Auto Safety. The auto safety agency since 2017 has been investigating some Hyundai and Kia vehicles for fire risks. The South Korean automakers have recalled more than 2.3 million vehicles since 2015 to address various engine fire risks.

The probe covers the 2011-2014 Kia Optima and Sorento; and 2010-2015 Kia Soul, along with the 2011-2014 Hyundai Sonata and Santa Fe.

Hyundai said in a statement it was co-operating and added it has been in "frequent, open and transparent dialogue regarding non-collision engine fires".