Is it permissible for prisoners whose prisons are 100 km away from their place of residence and who are prevented from performing Friday prayer to shorten and combine prayers?

If a person is imprisoned far from his homeland, at a distance allowing for qasr (shortening prayers), and he does not know when he will be released, then he is considered a traveler. He is permitted to shorten prayers and combine them when needed. However, if he knows he will stay for more than four days, he is not allowed to avail himself of the traveler's concessions, according to the majority of jurists. The travel distance that permits concessions is approximately eighty kilometers. Whoever has not specified the duration of their stay, or is awaiting the fulfillment of a need, may avail themselves of the traveler's concessions, even if their stay is prolonged.

Jumu'ah prayer is not obligatory upon prisoners inside their cells. However, if they are able to pray it in the prison mosque, it becomes obligatory for them. They should pray the five daily prayers in congregation inside their cells if they cannot pray in the prison mosque. If they have been sentenced to imprisonment and have settled in one place, they are considered residents and are not allowed concessions, unless the prison administration permits them to pray in the prison mosque. But if they are transferred from one place to another without knowing the duration of their stay, they are permitted to avail themselves of the traveler's concessions.