Terror warnings put Indonesia on alert

Islamic groups also offered to help protect churchgoers.

Maj. Gen. Firman Gani, the Jakarta police chief, said Jemaah Islamiyah terrorists might use the holidays to retaliate for the death last month of bomb-making expert Azahari bin Husin. He was gunned down in a police raid.

His shadowy network is blamed for at least five suicide bombings targeting Western interests since 2002 including Oct. 1 restaurant attacks on Bali island that together killed more than 240 people.

It is also accused in Christmas Eve church bombings five years ago that left 19 dead.

"The terrorists have said they will use the momentum of Christmas and the New Year celebrations to carry out attacks," Gani told reporters, adding that there were also indications that Jemaah Islamiyah may be changing its tactics.