The news came as four other people were arrested today in an early morning police raid in Italy.
It was reported that Cremona prosecutor Roberto Di Martino, who has been leading the operation for three years, confirmed that Gattuso, 35, and retired Lazio player Cristian Brocchi allegedly were part of a ring that fixed Serie A and other Italian matches at the end of the 2010-11 season.
Former AC Milan and Italian world cup winner Gattuso – whose real name is Gennaro – reportedly had his home searched as part of the investigation.
Mr Di Martino said: “Gattuso and Brocchi were connected to the case by the use of phone taps.” However, he could not confirm that anyone had been charged.
It was reported that the four people arrested are Salvatore Spadaro, Francesco Bazzani, Cosimo Rinci and Fabio Quadri; each of whom allegedly helped connect fixers to players.
Gattuso spent around a year at Rangers.