The fact that the vessel was able to stray so close to the rig has sparked questions as to the project's security with the operator saying it had no plans to increase naval protection during the short term heightened security status/scare involving Indonesia and Australia that has followed the Bali bombing.

Vessels are not permitted within 500 metres of any offshore facility but it is understood the fishing vessel was virtually beneath the Ensco 104 rig, formerly the Chiles Discovery, before being moved on. It is drilling the production wells for Phillips Petroleum on the Bayu-Undan project in the Zone of Cooperation in the Timor Sea.

Phillips area manager, Blair Murphy, was able to confirm the incident but said fishing boats straying close to offshore work was not an unheard of incident although not regular.

The incident sparked the rumour that a terrorist attack had actually occurred and had been repelled, a claim strongly denied by Phillips and all companies involved in the project.

He said however that Phillips was unable to reveal any details of the increased security measures he said it had introduced, in order to protect the installation and its workers.

"We have a heightened awareness in the area and are comfortable with what we have planned," he said. Mitchell said he was comfortable having the single vessel provide support services for the platform.

He was not aware of any increased early warning surveillance capabilities and management at marine support companies have stated there are no weapons on board the tender vessel.

Historically, high pressure fire hoses have been used to repel illegal boarders from vessels and installations.

The SAS Regiment is traditionally Australia's counter response group, but concerns have been aired recently that with the drain the Afghan "War against Terror" has put on the SAS, Australia's oil and gas industry is more vulnerable to attack than previously before.