If the mass gathering is a demonstration that follows the rules, it is not a problem, the police chief noted.
However, the recent demonstration had turned into unrest.
The security forces will secure the presidential inauguration which is the constitutional mandate.
If the authorities cannot secure the constitutional mandate, the impact will be bad, namely disturbing the pillars and the integrity of the state, he said.
Besides, the state guests, heads of state, heads of government and special envoys from other countries will be attending the inauguration.
"We also think that our nation must be respected and should be seen as a great and peaceful nation," he remarked.
Some 30 thousand police and military personnel have been deployed to tighten security at vital installations ahead of President Joko Widodo's swearing-in for his second and final term on October 20.
"The joint personnel from the Indonesian Military (TNI) and the National Police (Polri) have strengthened the security at vital installations such as the airports, power plants, Pertamina's logistical locations, the financial centers and others," The TNI Commander Air Chief Marshal Hadi Tjahjanto earlier said after the call ceremony.
The security apparatus had been put into place since Thursday morning, October 17, with as many as 30,000 soldiers guarding vital installations.
"What we see this morning are 30,000 soldiers from TNI and Polri who are ready to carry out security duties," he said. (INE)
Related news: Thirty thousand personnel deployed prior to presidential inauguration
Related news: Students urged to not demonstrate prior to presidential inauguration
EDITED BY INE