Anonymous has released a tape of the call in which detectives give details of alleged hackers being tracked.

The FBI said the information had been obtained illegally.

Later, it emerged Anonymous had also hacked the websites of US police forces and the Greek justice ministry.

The FBI said in a statement: "The information was intended for law enforcement officers only and was illegally obtained. A criminal investigation is under way to identify and hold accountable those responsible."

London's Metropolitan Police's central e-crime unit said the matter was being investigated but that no operational risks had been identified.

'Highly embarrassing'

Anonymous is a loose collective of "hacktivists" which has been responsible for cyber attacks on various companies, governments and individuals in recent years.

The recording of the conference call - said to have taken place on 17 January - was posted on YouTube, along with an email allegedly sent by the FBI to law enforcement agencies in various countries giving details of how to dial in to it.

It invited them to "discuss the on-going investigations related to Anonymous, Lulzsec, Antisec, and other associated splinter groups".

It was unclear how Anonymous obtained the recording, but a lawyer for one of the suspects discussed in it told the BBC it appeared to have been taken as an audiofile from an intercepted email, rather than having been eavesdropped on.

A comment on one of the Twitter accounts linked to Anonymous, AnonymousIRC, said: "The FBI might be curious how we're able to continuously read their internal comms for some time now."

The recording features about five men calling from the UK, Los Angeles and Washington, who discuss in detail the ongoing investigations into hacking and action being taken against suspects.

Among them are several British men accused of being behind cyber attacks in the US and UK.

The police give the online pseudonyms of suspects but the real names have been bleeped out of the recording.

When the British detectives discuss delaying some arrests while US investigations are being carried out, the FBI agent thanks them for their co-operation.

The British detective replies: "We're here to help. We've cocked things up in the past, we know that."

BBC security correspondent Frank Gardner says the recording will be highly embarrassing for the cyber crime detectives.

'More mayhem'

Later on Friday, Anonymous said it was behind an attack on a police website in the US city of Boston.

A message posted on the site before it was taken down said it had been targeted in response to "police brutality" towards the Occcupy Wall Street movement and warned there was "plenty more mayhem to deliver".

Meanwhile police in Salt Lake City, Utah are investigating a cyber attack on Tuesday on a site used by residents to report crimes.

The site was taken down and Detective Dennis McGowan said police were "knee deep in trying to get a feel for the extent of the problem".

Hackers operating under the Anonymous name also took over the website of Greece's justice ministry on Friday in a protest against the country's signing of a global copyright treaty and the government's handling of the economic crisis.

The website was replaced with a video of a figure wearing the symbolic white mask of Anonymous supporters, saying: "Democracy was given birth in your country but you have killed it."

报道称，美英两国最重要执法部门之间的会议遭黑客窃听，引发安全专家关注。安全风险评估公司“Rapid7”的凯里说，执法部门使用未经加密的不设防渠道沟通，假设会议内容涉及恐怖袭击，窃听者又是恐怖分子的话，后果将不堪设想。

据报道，这段长17分钟，遭黑客公开的电话录音中，可清楚地听到FBI和苏格兰场探员讨论针对黑客活动的调查进展，提到两名被控的英国黑客，以及如何拖延聆讯过程以配合对方调查。会上探员说笑，如形容一名15岁英国黑客“有点白痴”，又互戴高帽，感谢对方协助办案。“匿名者”组织公布录音时，将部分黑客真名做了消音处理。

除了录音，“匿名者”组织还公开了会前4天FBI发给英国、法国、德国、爱尔兰、荷兰及瑞典执法部门的邀请电邮。电邮写有会议举办的时间以及登入密码，相信“匿名者”就是藉此公然将会议进行录音的。

FBI强调其本身系统并未遭入侵。局方消息透露，可能是接收电邮的欧洲执法部门将电邮转寄到不受保护的私人邮箱，因此遭黑客窃取。苏格兰场表示正调查此次事件，称暂时无证据显示遭入侵。

“匿名者”事后在社交网站“推特”(Twitter)上张贴录音及电邮的链接，并发文称：“FBI现在可能会很奇怪我们如何能一直偷听他们的内部通讯。”有法国执法部门消息称，事件或导致日后国际执法部门更为谨慎，减少在电话会议上交换信息。

华译网翻译公司转载