India, Jan. 20 -- Iran's deepening political crisis took a dramatic turn after hackers breached the country's tightly controlled state television network. For a brief but powerful moment, Iranian viewers saw anti-regime messages urging security forces to abandon the clerical leadership and stand with protesters.

The hacked broadcast featured footage supporting exiled crown prince Reza Pahlavi and came as Iran faces massive nationwide protests, a soaring death toll, and a near-total internet shutdown.

The incident has raised serious questions about the regime's grip on power, internal fractures within security forces, and growing fears of international involvement.

During the interruption, viewers saw messages calling on security forces...