"We know the terrorist cells are still active, they are still hiding, recruiting, networking, trying to find new funding and even planning ... for another strike," Indonesian President Susilo Bambang Yudhoyono warned on Monday.
"Last night, I instructed the security minister, the head of the intelligence agency and the police chief to conduct more active operations into the detection and prevention [of the] act of terrorism that may happen this year ... in the months of September and October," Susilo added in a speech to newspaper editors in Jakarta.
Susilo also said bomb-makers from the al-Qaida-linked Jemaah Islamiyah network posed a threat to the world's most populous Muslim nation.
Indonesia has been hit by a string of attacks in recent years, including the 2002 Bali bombings, the 2003 bombing of the JW Marriott hotel and the September 2004 blast at the Australian embassy.
The high-profile attacks killed a total of 225 people.
Jemaah Islamiyah is blamed for the attacks.
The president, a secular former general, said he also wanted to reverse any perceptions that Islam in Indonesia was
becoming more hardline.
"You may read from time to time the voice of small radical groups. But this voice will not change the fact that mainstream Indonesia will continue to be moderate, tolerant and democratic," Susilo said.
"We will strengthen the hands of the religious moderates," he added.
Susilo: We will strengthen the
hands of religious moderates
He did not say how he would do this, but Indonesia's image as a moderate Muslim nation has taken some hits in recent months.
In late July, Indonesia's top Islamic council issued a religious edict forbidding pluralism, any liberal interpretation of Islam and mixed marriages.
That legally non-binding fatwa by the Indonesian Ulama Council (MUI) was heavily criticised by many moderate clerics.
Muslim hardliners in parts of the country have also recently forced the closure of several churches, claiming they did not have licences to operate. Police have taken no action.
Embassy bomb scare
Also on Monday, the British embassy was evacuated after a suspicious item was mailed to the mission, but police said it was only a personal package that contained a disc player and biscuits.
Security is tight at most Western embassies in Jakarta, after several major bombings against Western targets in the past few years in Indonesia, especially the bomb attack last September outside the Australian embassy that killed 10 people.
"We know the terrorists cells are still active, they are still hiding, recruiting, networking, trying to find new funding and even planning ... for another strike"
Susilo Bambang Yudhoyono,
Adjutant Commissioner Gatot Kristianto, head of police security for foreign embassies, said the package was mailed from central Java to a local employee at the mission.
"When it was scanned, security guards saw a cable so they
suspected it was an explosive device. After the bomb squad
checked it, they found no explosives. It contained a Walkman, biscuits and some cashew nuts," said Kristianto.
British embassy press officer Faye Belnis said the mission had been evacuated as a precaution.