The US embassy said yesterday the Malaysian government had warned of a security threat in Kuala Lumpur, as police said a blast at the Australian high commission a day earlier had not been an attack.

"The American embassy in Kuala Lumpur has received information from the Malaysian government regarding an anonymous, unverified threat in central Kuala Lumpur," the embassy said in an advisory to US citizens here.

"The US government is working with the Malaysian authorities to try to verify this information. American citizens may notice an increase in security around Kuala Lumpur as a precautionary measure."

A police spokesman at the city district headquarters said they were not aware of the threat.

However patrols had been stepped up after a blast at the Australian High Commission late Wednesday, he said, even as other officials said the explosion had not been caused by an attack.

Security sources said they did not think the blast and the government's warning were linked.

Car backfiring

Police near Australian embassy and passers-by had heard "a loud bang and saw a flash from a vehicle passing in front of the high commission" around 8:00 pm Wednesday, district police chief Kamal Pasha Jamal told AFP .

The bomb squad, forensics team and tracker dogs were immediately deployed to the scene and the road in front of the embassy was cordoned off, but no injuries or damage to property were reported, he said.

"No, definitely not a terrorist attack. We found no sulfur or anything to indicate it was a bomb. It may have been a car backfiring," he said.

"There is no threat. The case is closed."

In Canberra a spokesman for Australian Foreign Minister Alexander Downer said details of the explosion were sketchy but he also dismissed it as a terrorist threat.

"We are going to seek a briefing from the Malaysian police but there is no suggestion of any specific threat to Australian interests," the spokesman said.

The high commission was attacked in March last year when someone in a speeding car threw a small explosive device into its compound.

Prudent approach

Security experts from International SOS in Singapore, a leading global security and medical provider, told AFP the organisation had also received information of an increase in the terror threat in Malaysia.

"We have received a similarly unverified report that indicates an increase in the threat from terrorism in Malaysia," said security specialist Grant Brown.

The company had deployed a member of its security team to Kuala Lumpur to verify the information, he said.

"While there has not been a major terrorist attack in Malaysia in recent years, we are advising a prudent approach in light of the Warden Message released by the US embassy," he said.

There have been no major terrorist attacks on Malaysian soil but the authorities here have detained scores of alleged Muslim militants accused of belonging to regional terror groups such as Jemaah Islamiah, which authorities say has links with the al-Qaeda network.

The police have set up a special security squad to protect foreign embassies. Most Western embassies here also have their own tight security systems in place.