The Fantasy Sports Trade Association received a grand jury subpoena Friday from a U.S. attorney's office in Tampa, Florida, according to the Wall Street Journal. An investigation by the Department of Justice and the FBI has reportedly been underway to determine the legality of daily fantasy sports games and whether they should be considered a form of gambling.

The announcement comes one day after the Nevada Gaming Control Board said unlicensed daily fantasy sports in the state must cease and desist, according to reports. The notice to licensees stated that daily fantasy sports (DFS) meet the requirements of a game or gambling game.