The FBI has opened an investigation into Uber over its “Hell” program, which the company allegedly used to track Lyft drivers from 2014 to 2016, according to The Wall Street Journal. The probe is being led by the FBI’s New York office in conjunction with the Manhattan US attorney’s office, the latter of which was already investigating Uber’s “anticompetitive strategies” since 2016, according to the report.

“We are cooperating with the investigation,” an Uber spokesperson tells The Verge. The company declined to offer any further comment.

One of Hell’s main schemes involved Uber creating fake rider accounts on Lyft, according to a report published in The Information in April. It then used those accounts as a window into its rival service, where it monitored how many Lyft drivers were available in certain areas at certain times. Armed with that information, Uber would fill apparent gaps in Lyft’s coverage in real time. The software got its name because of the way it mirrored Uber’s “God view,” or, later, “Heaven view,” which employees used to track the company’s own drivers and riders.

Another part of the program was used to identify drivers who used both Lyft and Uber. Uber reportedly used that information to target these drivers with incentives to lure them away from Lyft. The company reportedly discontinued the use of Hell in 2016.

Earlier this year, a former Lyft driver filed a class action lawsuit against Uber over its use of the Hell. The suit alleged that Uber’s secretive tracking program violated various privacy and communications acts, but it was ultimately dismissed last month.

The investigation into Hell is not the only one Uber’s newly minted CEO has to worry about. In May it was reported that the US Justice Department opened a criminal probe into the company for its use of “Greyball,” software that allowed it to evade local regulators in towns where the company wasn’t licensed to operate. The Justice Department is also investigating whether Uber violated the Foreign Corrupt Practices Act.

Update September 8th, 10:26AM ET: Added comment from Uber spokesperson.