Pakistan, April 24 -- Iran's exiled Crown Prince Reza Pahlavi was splattered with red liquid on Thursday as he left a building in Berlin.

Pahlavi had just departed a news briefing, during which he criticized the ceasefire between the United States and Iran, when the incident occurred outside Germany's federal press conference building. He appeared unhurt and waved to his supporters before he got into a car that drove away. Police said the liquid appeared to be tomato juice. The alleged perpetrator, whose name was not released in line with German privacy rules, was immediately detained by police.

Pahlavi, 65, is the son of Iran's former shah, who was so widely hated that millions took to the streets in 1979 to force him from power. Never...