The statements said foreigners could be targeted in attacks, but they did not say what intelligence the alert was based on. Australia has issued a similar warning.
Indonesian officials however say they have seen no evidence an attack is imminent.
"The Australians and the Americans can say what they want, that is democracy," said Col. I Ketut Untung Yoga Ana, Indonesia's police spokesman.
"But up until now, we have not seen any frightening signs."
Searched
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Indonesia says it has seen no indication
that an attack is imminent [EPA] |
Despite the warnings Christians across Indonesia flocked to church for Christmas services.
"Life and death are in the hands of God,'' said Lolita Utamisari after attending mass at Jakarta's main cathedral on Monday, where worshippers were thoroughly searched.
"We could die anytime, anywhere. Therefore, there is no need to be scared."
On the mostly Muslim island of Lombok, worshippers and church officials said the increase in authority was unwanted and that churches were forced to pay for the security, state news agency Antara reported.
Indonesia’s underpaid police and military have been accused of demanding money from religious minorities in exchange for protection, whether they want it or not.
Churches in Indonesia have been hit by a series of attacks since bombings at churches around the archipelago killed 19 people on December 24, 2000.
Since those bombings Jemaah Islamiyah, a South-East Asian militant group which Western intelligence agencies say has links to al-Qaeda, has staged four major attacks on Indonesian soil.
The deadliest attack was the 2002 nightclub bombing in Bali, which killed 202 people, most of them foreign tourists.
Indonesia is the world's most populous Muslim nation, but has a sizeable Christian minority though to account for roughly 10 per cent of Indonesia's 220 million people.