Prosecutors of a new organised crime unit in Panama raided the headquarters of law firm Mossack Fonseca, which is facing investigation after thousands of its documents, dubbed the Panama Papers, were leaked.

The Panama Papers, which run to more than 11 million documents and are described as the biggest leak of its kind, show that the law firm helped many wealthy people in different countries in setting up offshore companies, some of which may have been used to avoid taxes.

The attorney general's office in Panama said in a statement that its newly created team to fight organised crime paid a second visit to Mossack Fonseca headquarters on 12 April. The team was led by second specialised prosecutor Javier Caraballo.

The raid was conducted "to obtain documentation linked to the information published in news articles that establish the use of the firm in illicit activities," the attorney general's office was quoted as saying in the statement.

On 11 April, the first round of raids was conducted at the offices of the law firm. They were led by prosecutor Ricauter González and included Mossack Fonseca's offices in Peru, located close to the Panama Embassy in the exclusive district of San Isidro.

The objective of the raids was to check on "how the company files were hacked," the attorney general's office said. The tax investigators also searched the firm's offices in Brazil and El Salvador. The law firm had filed a complaint against the security breach soon after media reports surfaced about its leaked documents.

The attorney general's office said the law firm has said in a statement that it is "always ready to cooperate with all authorities requesting information through appropriate channels."

Mossack Fonseca, director Ramon Fonseca, has denied any wrongdoing. He has said the firm suffered a hack on its database and described the leak as "an international campaign against privacy".

Many high-profile figures, including Prime Minister David Cameron, were affected by the leak. It was revealed that the prime minister's late father Ian Cameron reportedly opened a network of offshore investment funds, from which he benefited to the tune of £30,000 ($42,779).

Following the Mossack Fonseca leaks, Panamanian President Juan Carlos Varela assured the international community that he will work towards making its financial sector more transparent, the Guardian reported. The president reportedly requested France to reconsider its recent decision to blacklist Panama.

The Panamanian government also announced the formation of a panel to review the country's legal and financial practices and suggest necessary changes. The panel will include 2001 Nobel Prize-winning economist Joseph Stiglitz.