Australia is taking seriously a video shown on U.S. television threatening an attack on Melbourne, the government said on Monday, but added it wasn't raising the national threat level from medium to high.
The tape, broadcast on Sunday and purportedly from a U.S.-born member of al-Qaeda, threatened Los Angeles and Melbourne on the fourth anniversary of the Sept. 11 attacks on the United States.
Attorney-General Philip Ruddock said a special taskforce was seeking a copy of the video tape to assess the risk to Australia's second largest city.
"Security agencies are working closely with their overseas counterparts to try and find further information about it," Ruddock told Australian radio on Monday.
"What it demonstrates to me is that we have been targeted in the past, we remain of interest to terrorist organizations. This may or may not be a real threat, it may well be a hoax but that matter has to be seriously examined."
According to Herald Sun, Russ Knocke, a spokesman for the Department of Homeland Security, said US authorities are trying to verify the tape but "there's no specific intelligence to verify or substantiate" the claims and threats in it.
"We are certainly aware that al-Qaeda seeks to strike the United States and our interests abroad," he said. "We maintain a strong and vigilant security posture."
Mr Gadahn is believed to have been the young American who appeared in another threatening tape about year ago.
ABC said the young man apparently converted to Islam at an Orange County, California, mosque as a teenager.
Los Angeles Police Chief William Bratton said his city has strong security measures already in place but is not upgrading them up because of this particular tape.
"We have a very robust counter-terrorism operation here in LA, similar to New York and Washington because we are always a prime target," Chief Bratton said. He added that Mr Gadahn seemed to be "a mouthpiece, a spokesperson, not an operative.”
Still of ABC TV