The United State embassy in Malaysia, closed since Wednesday due to what it said was a 'specific and credible threat', reopened today under tight security.

The embassy said in a statement that it resumed normal operating hours this morning.

"We are extremely grateful to the government of Malaysia and in particular, the Royal Malaysian Police, for the support and protection they have provided to the US embassy," it said.

Embassy spokesperson Frank Whitaker said the change in the security situation at the embassy "has been enormous" since last week when the US was commemorating the first anniversary of Sept 11 terror attacks.

"We reviewed the security situation and because we have good security measures, we decided to reopen the embassy," he said when asked if the threat to the embassy security had lessened.

Last Tuesday, the embassy issued a short statement announcing its closure the following day amid anticipation of a security threat. It said it was extending the closure until further notice on Sept 11.

Scores of armed personnel from the police general operations force have since been stationed outside the embassy which is located in Jalan Tun Razak, Kuala Lumpur.

Security fears have also forced the closure of the US embassies in Indonesia, Vietnam, and Cambodia since Wednesday. The embassy in Jakarta and its consulate in Surabaya had reopened today but the rest remained shut.

A CNN report on Friday said the information about the security threat came from Omar al-Faruq, a Kuwaiti national and an alleged al-Qaeda operative who was arrested in Indonesia about two months ago and was turned over to the US in recent weeks.

Plot details

Intelligence officials were quoted as saying that Omar had "only recently started to talk" and revealed details of the plots to attack a number of US facilities in Southeast Asia which "specifically fitted into what we already had".

A senior state department official had said US embassies in the Asian region were just part of the American facilities that were under threat of "a possible suicide bomber" and "vehicle delivered bombs cars and trucks".

The news report added Omar has been "tasked with pushing Philippine cells of al-Qaeda to acquire over 20 tonnes of explosives to be used for suicide bombing attacks against US and western interests in the region".

The Washington Post on the same day also raised question on the missing four tonnes of ammonium nitrate purchased by former Malaysian army captain Yazid Sufaat for an al-Qaeda-linked plot to blow up the US embassy in Singapore.

Missing chemicals

A Malaysian official was quoted as saying that "as far as we know, the ammonium nitrate was sent to Batam island (of Indonesia). We don't know what happened after that".

Yazid has been held under the Internal Security Act which allows indefinite detention without trial in the Kamunting detention centre in Perak. He had admitted buying the chemical fertiliser but stressed that it was just a business deal with a quarry in Indonesia.

Last week, Foreign Minister Syed Hamid Albar had said Malaysian government was upset because the US embassy failed to inform them on its intended closure and the reasons behind the move.

"We regret their action as it sends a negative message about our country. If they have a real problem, we are prepared to enhance security at any time," he said.

The minister also said that the government maintains tight security at all foreign missions and embassies and there was no reason for the US to panic and close its embassy.

But the US embassy said it had notified the government about the closure and the nature of the security threat.