What is the ruling on prisoners performing Friday and congregational prayers behind a single imam who leads them while they are in their cells, by means of a loudspeaker?

The Council of Senior Scholars has issued a fatwa stating the impermissibility of prisoners gathering behind a single imam for Jumu'ah (Friday) and congregational prayers via loudspeakers inside their cells, given that Jumu'ah prayer is not obligatory upon them as long as they are unable to hasten to it. As for the five daily prayers, each group should pray in congregation inside their cells if it is difficult to gather them in one place. Whoever is able to attend Jumu'ah prayer in the prison mosque, if one exists, should pray it with the congregation; otherwise, it is waived for him and he should pray Dhuhr (noon prayer).