Scotland Yard has launched an investigation into claims that calls Teampoison hackers illegally recorded phone conversations between anti-terrorism officers.
"We are aware of an issue whereby telephone conversations relating to the Anti-Terrorist Hotline have been recorded," a Scotland yard spokesman said.
"Officers are currently looking into the matter and appropriate action will be taken."
Teampoison told Sky News that they used Skype and a number of proxy servers during the attack.
"It took no skill whatsoever, it was pretty much an in-and-out job, it was pretty much simple. They use an old phone system," a member of the group said.
"If we wanted to go ahead and listen to their calls it would be easy for us. we could pretty much do it at any time and any place."
In the recording conversation posted on YouTube, two people are heard discussing One person said that the hotline received more than 700 calls from the group. "We have been subjected to a barrage of calls from a group called Teampoison. We have had about 700 calls over the last couple of nights. One of the conversations I had last night was leaked on YouTube.
"Everyone else calling was effectively shut out and could not through at all."
The announcement came after reports that hackers affiliated with the group have attacked the MI6 in protest at what is said was the detention of innocent people on terrorism charges.
The group, which recently defaced Croatia's Nato website in protest at Western military intervention in Libya in 2011, launched a "phone bomb" on MI6's London office, making non-stop calls for 24 hours.
"Every time they picked up the phone the server would play a robot voice which said 'Teampoison'," the leader of the group, called Trick, told Softpedia website.
The attack amounts to a phone denial of service akin to the Anonymous collective's most common hacking tool, the Distributed Denial of Service (DDoS).
After the phone bomb, Trick made a prank call goading MI6 officials who threatened to alert the FBI.
"My name is Trick, I'm from Teampoison, my name is Robert West," says the voice. "I got some terrorism for you here."
The officers ask him where he is. "I'm in the UK," Trick replies. "I don't brush my teeth, I like tea, I'm from the UK."
"What's your actual philosophy?" asked the official. "I'm not familiar with it."
"Our philosophy is pretty simple, it's knowledge is power," said the hacker. "And, uh, f**k the po-lice."
"Yeah..." replies the official.
For further news on Teampoison's recent activities, check out the IBTimes UK Cyber Warfare section.