A hacking forum described as the world's most savvy English-speaking online watering hole for criminal computer gurus has been smashed, US and European officials said Wednesday.

A total of 28 people were arrested and 12 were charged.

Darkode, as it was called, was a password-protected forum where hackers and other cyber criminals conferred to buy, sell, trade and share ideas and tools for breaking into people's computers and other devices, the officials said.

"The Darkode forum was the place to go to if you were an English-speaking cybercriminal," Europol said in a statement.

Darkode was taken down this week in an operation by 20 countries including the United States and such far flung nations as Australia and Cyprus.

It was the largest coordinated international law enforcement effort ever directed at an online cyber-criminal forum, the Justice Department said.

US officials in Pennsylvania, Wisconsin, Washington, DC and Louisiana brought charges against 12 people. It did not say if they were actually arrested.

The charges were part of the 20-member coalition's effort to charge, arrest, or search 70 Darkode members and associated around the world, the Justice Department said.

Darkode had 250 to 300 active users, Europol said. A total of 28 people were arrested in this week's raids, it added.

Membership in the forum was by invitation only. Prospective members had to show they had skills or products to present to the group, officials said.

Darkode was brought down thanks to FBI infiltration of its membership, the US Department of Justice said.

"Through this operation, we have dismantled a cyber hornets' nest of criminal hackers which was believed by many, including the hackers themselves, to be impenetrable," US Attorney David Hickton said.

The operation was led by the FBI and backed up by Europol's European Cybercrime Centre, known as EC3.

"The curtain fell on the cybercriminal forum when the site was taken down and a banner was put up online indicating that the FBI, EC3 and international partners had control over the site," the Europol statement said.

Darkode was among the top five of the most prolific criminal forums worldwide, Europol said. It said this list was otherwise dominated by Russian-speaking criminal platforms.