Criscito - who currently plays for Zenit St Petersburg in Russia but has represented Juventus and Genoa in the past - had his room searched at Italy's Coverciano training camp after police arrived at 6.40am on Monday morning.
Police also spoke to Juventus defender Leonardo Bonucci over allegations during his time at Bari, but he is not under formal investigation so will go to the tournament.
"I have talked with Bonucci, he has already been heard by prosecutors in Bari. He is calm and so are we," Prandelli added.
"At the moment he has not received any communication. If Bonucci is OK, he will be in the list of 23 for the Euros."
Italian federation vice-president Demetrio Albertini has now confirmed that the defender will not travel to the finals in Poland and Ukraine as he wants to "clear his position with prosecutors".
"It has been a decision agreed between (coach Cesare) Prandelli and the federation," Albertini told reporters.
"He (Criscito) was also sorry for the repercussions on the national team and on the dressing room. He explained some things to me and I believe his version and in his innocence."
Criscito, who prosecutors allege was photographed in a restaurant with match-fixing suspects while still a Genoa player, told reporters: "I have nothing to do with this. I was only out for dinner with some Genoa fans".
"I am not taking Criscito because he would have been under pressure which no human being can bear," Prandelli said.
"The other reason is that he could have been summoned by the prosecutor at any moment, before a match."
Italian police investigating a football match-fixing scandal also placed Juventus trainer Antonio Conte under investigation and arrested the captain of Lazio Stefano Mauri and former Genoa midfielder Omar Milanetto, authorities said on Monday.
A police statement said five people had been arrested in Hungary on suspicion of being part of an illegal international betting ring headed by Singaporean gambling identity Tan Seet Eng, who was arrested in December.
Police in the northern city of Cremona said they had made 19 arrests and were investigating Conte, fresh from his triumph in leading Juventus to the Italian Serie A championship for the first time since the club was relegated in 2006 in an earlier match-fixing scandal.
It said searches were conducted at the homes of a number of players, trainers and administrators of clubs in Serie A, Serie B and the lower division Lega Pro on suspicion of involvement in match-fixing on behalf of international criminal organizations.
Monday's operation was part of "Last Bet", a wider investigation into match-fixing in Italian football which has already seen a number of arrests of current and former Italian players.
"In this part of the investigation, indications have emerged of manipulation in matches from the 2010-11 Serie A championship, including games between Lazio and Genoa and Lecce and Lazio," Raffale Grassi, director of SCO, the police service responsible for the investigation told SkyTG24 television.
In June last year, the Interior Ministry set up a special match-fixing task force in response to a number of high profile cases.
Former Atalanta captain and Italy midfielder Cristiano Doni, was banned for three-and-a-half years in August for his part in the 'Calcioscommesse' match-fixing scandal involving Serie B matches last season.
Atalanta, promoted from Serie B, were deducted six points in the top flight this season as a result of the scandal.
Former Lazio and Italy striker Giuseppe Signori was banned for five years and 15 other players were banned for between one and five years for their part in the same scandal.
The following 25-man squad has been called up ahead of Tuesday's friendly against Luxembourg - however it will be trimmed to 23 by noon on Tuesday, with Andrea Ranocchia and Mattia Destro expected to be left out.