The decision to isolate Mario Castagnacci and Paolo Palmisani was made when authorities feared that other inmates may have sought revenge for their actions, which resulted in Morganti’s death.
Castagnacci and Palmisani, who have been identified as stepbrothers, brutally attacked Morganti outside a bar on Saturday in Alatri, in the Lazio region.
Morganti, who was allegedly defending his girlfriend when he was attacked, died in hospital on Sunday after two days of suffering from serious injuries.
The chief prosecutor Giuseppe De Falco said on Tuesday that the case is "appallingly serious because futile motives, a row over a drink, led to the death of a good, innocent lad".
"The two who have been arrested mix in criminal circles, and we can’t forget that they think they have control over that territory; we are verifying if the violent behaviour was also caused by alcohol and drugs abuse,” he added.
De Falco stated that Morganti was attacked several times after an initial altercation, and that seven people, including the two stepbrothers, were under investigation.
Castagnacci and Palmisani are suspected of inflicting the fatal head wounds in the last of the attacks.
Castagnacci's lawyer Tony Ceccarelli announced on Wednesday that he would be renouncing the job.
