Global One (G1)— Twenty people linked to birth tourism in the United States have been indicted with a range of charges on Jan. 31.

Authorities said it was the largest ever crackdown on the business, in which travel agents help pregnant women give birth on U.S. soil to make their children American citizens.

The accused allegedly owned and operated You Win USA Vacation Services, USA Happy Baby and Star Baby Care and catered to Chinese women.

The agents reportedly coached pregnant women to lie about their visit to the U.S. According to the Los Angeles Times, the women first travel to Hawaii to blend in with tourists before they go to other parts of the country to give birth.

The women reportedly paid as much as $100,000 for it.

Meanwhile, officials reportedly said they won’t challenge the children’s citizenship as they are citizens nonetheless under U.S. law.