India’s tax agency has placed 10 of the biggest casinos in the state of Goa under investigation over allegations that they have been evading service taxes, according to The Economic Times of India report.

Tax officers from India’s Directorate of Revenue Intelligence came knocking on the doors of the supposed erring casinos to serve their respective tax notices. The government is demanding these 10 casinos to pay the service taxes on their license fees.

India’s intelligence arm accused the casinos of failing to pay tax on license fees from 2014 to 2016. The government argued that the law clearly stated that the casinos were required to remit 15 percent tax on the license fees to be in business.

Data showed that Goa hosted at least six land-based casinos while the remaining were floating casinos. The brick-and-mortar casinos were situated in the Indian state’s five-star hotels, where only visitors from other states are welcomed.