(CNN) -- Protesters gathered in Iran on Friday for a demonstration to observe an annual holiday that marks the country's solidarity with Palestinians and calls for the end of Israel occupation.
One notable absence was Iranian opposition leader Mehdi Karoubi, whose security force feared for his safety and advised him to stay away, his son said.
About 50 people surrounded Karoubi's home Friday morning -- shooting paint balls and shouting chants against him and the opposition movement, the son said.
Attackers targeted his father's house repeatedly to stop him from participating in Friday's events, said Mohammad Taghi Karoubi.
The opposition leader's website said his apartment had come under attack four times in four consecutive days.
The site said the head of his security team was in a coma after being beaten as he tried to talk with a group of attackers who broke into the apartment complex Thursday.
CNN
