Warships and military aircraft patrol Malacca straits

Warships in the Southeast Asia were put to sea as Malaysia, Singapore and Indonesia increased maritime and air patrols following threats of possible terror attacks in the straits of Malacca.

The three countries have raised their security levels and mounted aerial reconnaissance of the narrow straits through which passes 30% of the global trade and 50% of oil shipments.

"All state alerts have been put at the highest level, not just for ships but also for security measures," the Malaysian and Singapore officials said.

The extraordinary steps were taken after authorities received a tip off that an unidentified militant group was planning to attack oil tankers in the busy waterway. Super tankers everyday passage the straits and even a small blast can block the waterway.

International Maritime Bureau piracy reporting centre's Asian region head Noel Chong has said it had been alerted about the threat by a foreign government agency and had passed this on to the relevant authorities in the three countries.

"This alert was not issued by us so we cannot tell you what level or how serious the threat is," he said.

The International Maritime Bureau has advised ships plying both the straits to be extra vigilant and conduct radar lookouts.

"Usually ships keep a lookout after dark to thwart pirate attacks, we are advising them to keep a 24-hour watch," Chong said. A top Malaysian maritime officer confirmed that authorities had received information indicating that Islamic terrorists were plotting to "wreck havoc" in the Malacca straits.

Chong said though piracy threat was common in both the straits, a terror threat was new. He said the warning didn't say which terrorist group was planning the attack or what kind of attack was feared.

The Singapore navy has issued an advisory warning of terrorist attacks against oil tankers in the waters but did not specify any groups.

The Malacca straits is one of the busiest shipping routes of oil shippers between the Persian Gulf and Asia-Pacific regions and over 90,000 ships passage through it each year.

The official said they were coordinating sea and air patrols in the area.

Malacca straits has been a hotspot for pirate-attacks, but security has improved substantially in the recent years, thanks to coordinated patrols by nations bordering the waterways and the navies of US and India.