Indonesian police are warning of a possible terrorist threat targeting dignitaries planning to commorate the 10th anniversary of the Bali bombings.

Police Brig. Gen. I Ketut Untung Yoga Ana said Wednesday that he received reports of "certain movement" of terrorists. He said security has been tightened at all entry points to the tourist island prior to Friday's ceremony.

Police did not provide any specific details about the threat.

Australian Prime Minister Julia Gillard is scheduled to attend the event commemorating the Oct. 12, 2002, attacks on two nightclubs. The bombs killed 202 people, mostly foreign tourists.

Friday's ceremony will be held at a park followed by a ground-zero memorial in Kuta. Former Australian Premier John Howard and survivors, as well as victims' families, are also expected to attend.