OLYMPIA, Wash. — Governor Inslee issued an executive order Friday that makes Washington one of several states to ban the sale of flavored vaping products.

Inslee announced the ban while conceding that it’s not clear exactly what’s caused hundreds of lung illnesses linked to vaping.

He says the ban will apply to products containing nicotine as well as the cannabis extract THC.

Inslee’s move comes as at least seven cases of severe lung illness related to vaping have been identified in Washington and more than 500 nationwide.

About a dozen deaths have been reported.

His order asks the Department of Health to issue the emergency rule at its next meeting in October.