Tens of thousands of conservative Muslims rallied in the Indonesian capital for the second major protest in a month against its minority Christian governor.
Police say 22,000 officers and 5,000 soldiers can be called on to ensure the demonstration stays orderly today.
Organizers have agreed to concentrate the protest around the national monument in central Jakarta to reduce disruptions.
A protest on November 4 against Gov. Basuki "Ahok" Tjahaja Purnama, who is being prosecuted for blasphemy, attracted 100,000 people. After nightfall it turned violent, with one death and dozens injured.
Ahok is an ally of President Joko "Jokowi" Widodo, and the accusation of blasphemy has animated their political opponents, including hard-liners who have used the issue to seize a national stage for their extreme agenda, which includes Shariah law.