Eleven Saudi princes were reportedly arrested for protesting at a royal palace in the capital Riyadh, according to local media on Saturday.
The princes gathered at the Qasr a-Hokm to demand the reversal of a royal decree suspending payments for their water and electricity bills and compensations for the execution in 2016 of a relative convicted in a murder case, online news website Sabq online newspaper.
The website, citing unnamed sources, said the princes were detained by the royal guards after they refused to leave the palace.
According to the news website, the princes were sent to Al-Hair prison in preparation to be put on trial.
The first official confirmation came late on Saturday from Saudi public prosecutor Sheikh Saud Al-Mujab, the official Saudi Press Agency (SPA) said.
The princes were arrested for disturbing public peace and are being held at Al-Hair prison, SPA reported.
Al-Mujab said "everyone is equal before the law", and those who do not follow rules will be held accountable "whoever it may be".
In November, Saudi authorities arrested dozens of royal family members, current and former senior officials in a massive anti-corruption sweep in the oil-rich kingdom.