Nearly two dozen state attorneys general penned a letter Monday to the leadership of Kia and Hyundai urging the carmakers to take action against the “crisis of thefts” they say is a result of the companies’ failure to equip vehicles with anti-theft immobilizers.

While available data suggests most types of violent crime are declining in the U.S., motor vehicle thefts have been steadily rising for several years. Kia and Hyundai vehicles represent a large share of stolen cars in multiple cities, data from police and state officials suggests.

The group of 23 attorneys general says that’s because Kia and Hyundai chose not to include anti-theft immobilizers as standard equipment in many vehicle models sold in the U.S. even though “every other car manufacturer” was doing so. The same Kia and Hyundai vehicles sold in Canada and Europe were equipped with immobilizers, the attorneys general said.

Hyundai Motor Company is Kia’s parent company. Hyundai spokesperson Ira Gabriel said the company is “committed to the quality and integrity of our products” and “plans to continue supporting the communities affected by this theft issue.” He said all vehicles meet federal anti-theft requirements.

Kia, Hyundai campaign ‘not enough,’ officials say

Kia and Hyundai recently announced changes like warning stickers, longer alarms and a software upgrade that aims to prevent the vehicles from starting during a method of theft popularized on TikTok and other social media channels.

Kia and Hyundai said they have contacted more than a million customers with information on the software update. They’ve also shipped tens of thousands of physical anti-theft steering wheel locks to hundreds of law enforcement agencies across the country to distribute to customers, among other measures.

The attorneys general said the campaign is “positive news” but “not enough.” They say the companies have responded slowly and not taken responsibility for the “crisis.”