(1) Without the means or right to communicate.
(2) Silenced.
(1) It seems rather suspicious that he's gone incommunicado .
(2) For example, as discussed previously in this report, a person could be held incommunicado indefinitely with no apparent opportunity for judicial review.
(3) I expect he'll be incommunicado for at least 2 weeks.
(4) We don't kidnap people and hold them incommunicado .
(5) The project from the 6th circle of hell has been put to bed (for the second time in a month) and, as far as work's concerned, I'm incommunicado for a week.
isolated
out of reach/touch
sequestered
unreachable
secluded