Pennsylvania Gov. Josh Shapiro (D) called on authorities to investigate billionaire Elon Musk’s million-dollar giveaway to registered voters in his state, as well as six other battlegrounds.

Recently, the technology investor has vowed to award $1 million a day to registered voters who sign a petition with the pro-Trump political action committee that Musk is supporting. Though the payout is tied to signature of the petition not registering to vote, come critics — including prominent election law expert Rick Hasen — have questioned the legality of Musk’s giveaway, considering that it is only open to registered voters.

Speaking with NBC News anchor Kristen Welker on Sunday morning’s Meet The Press, Shapiro said Musk’s actions were “deeply concerning” while noting that “dark money is flowing not just into Pennsylvania, but apparently now into the pockets of Pennsylvanians.”