Seven people have been arrested in Malaysia for spreading hoax warnings of terrorist attacks over the internet.
Malaysia has been sensitive to scares since the Bali bombing
They are alleged to have sent e-mail messages claiming that targets including the world's tallest buildings, the Petronas Twin Towers in Kuala Lumpur, would be bombed.
Police say they are still hunting for the person who started the scare.
Six of the seven people arrested by Malaysian police were women.
They are accused of both spreading false news about possible terrorist attacks over the internet and of causing public alarm.
The seven were held under Malaysia's tough Internal Security Act, which allows for indefinite detention without trial.
If found guilty, they could face up to one year in prison, although for now all have been released on bail.
The messages claimed that tourist destinations - night clubs, shopping centres and other places popular with Westerners in Malaysia - would be bombed.
One of the recipients of the e-mails was the Australian High Commission in Kuala Lumpur.
Police are still looking for the person who started the e-mail rumour.
The hardline response shows just how sensitive Malaysia is to such scares in the wake of the Bali bombing in October, in neighbouring Indonesia, which killed more than 180 people, most of them foreign tourists.
Security in the capital outside embassies and around areas frequented by visitors has been stepped up since the attacks in Bali, while the government says the number of foreign visitors to the country has fallen by up to 30%.
Tourism is Malaysia's second-largest source of foreign earnings, and the government is anxious to send out the message that Malaysia remains a safe destination.
It has used the Internal Security Act to arrest more than 70 suspected Islamic militants in the last 15 months and says it has effectively neutralised the threat to its security.