A team spokesperson told Crash.net: "At the moment we can only confirm that Giovanni is under investigation.
"He is stopped at the Police in Lugano.
"As soon as possible we will give you all the information about the future of the team."
Italian entrepreneur Cuzari runs Yamaha machinery for Stefan Bradl and Loris Baz in the MotoGP Open class, plus Simone Corsi and Lorenzo Baldassarri on Kalex equipment in Moto2.
The MotoGP summer break is currently underway, with the next round at Indianapolis on August 7-9.