Bahrain opposition calls for inquiry into aluminium producer Bahrain's opposition has called for an independent investigation into state-run Aluminium Bahrain (Alba) after a corruption trial collapsed in London last week. Al-Wefaq, which has been at the forefront of protests in Bahrain, says losses to the public purse should be investigated by the government. "The Bahraini people lost money," said Abdul Jalil Khalil, a Wefaq spokesman. We need an independent investigation here in Bahrain to look into this as we are talking about more than $3bn - this is not an easy figure. Billionaire Victor Dahdaleh did not dispute that he paid £38m to Sheikh Isa bin Ali al-Khalifa, Alba's former chairman and a close adviser of the prime minister, to win $3bn of contracts for companies including Alcoa of the US. Mr Dahdaleh's lawyers argued in court, however, that the payments were not corrupt because they were known about and approved by Alba's government-controlled board. A letter from the Bahraini government to the UK's Serious Fraud Office and attorney-general, confirming that Alba's board was aware of the payments, may have helped end the trial in London but has redoubled anger among the opposition about official collusion with dubious practices. The sensitive case has been ignored by Bahrain's media, apart from limited reporting in the opposition-linked newspaper al-Wasat. Since widespread pro-democracy demonstrations were crushed in 2011, the Shia-led opposition has kept up calls for reform, citing corruption as one of the main grievances. The Bahraini government has been criticised for rights abuses in its attempt to end protests. Amnesty International said on Monday the authorities were arresting and torturing children as young as 13 on suspicion of participating in demonstrations. Calls for the prime minister, Sheikh Khalifa bin Salman al-Khalifa, to step down because of corruption allegations have been fiercely resisted by the minority Sunni community, which accuses the opposition of taking its orders from neighbouring Iran. The UK's SFO accused Mr Dahdaleh of "grand scale" corruption and said he was a "power broker" who amassed great wealth by "creaming off 10 per cent" of the contracts he helped negotiate for companies such as Alcoa. He was charged with eight counts of corruption and money-laundering between 1998 and 2006, under an old 1906 law. This law has since been replaced with the 2011 UK Bribery Act. Sheikh Isa was a named co-conspirator in the SFO's indictment but the court heard the SFO had no way to compel him to take part in the trial as no extradition treaty existed between the UK and Bahrain. A key defence to the old bribery laws is so-called principal's consent: if payments are known about by the so-called principal of an entity - in this case, Alba's board and the government of Bahrain - the payments cannot be construed as corrupt. Bruce Hall, Alba's former chief executive, has pleaded guilty to corruption and will be sentenced shortly. During his cross-examination, he agreed with the description of tensions in Bahrain, where "the royal family is all-powerful" and where "nothing of significance happened in Bahrain without the approval of the prime minister." Mr Hall described Alba's board as "dysfunctional," agreeing with the premise that the majority Bahraini members "accepted that what Isa and the prime minister said, went." The trial also highlighted tensions within the ruling family. Sheikh Salman bin Hamad al-Khalifa, the reformist-minded crown prince, led attempts to reform Alba well before the unrest of the Arab uprising reopened Bahrain's sectarian divide. The court heard that Mr Hall was summoned to the crown prince on his appointment as chief executive in 2001 and asked to report any corruption he might witness. But Mr Hall said that he felt he could only report to the crown prince if Sheikh Isa knew. A turning point that helped hasten the trial's collapse was a letter from one of Bahrain's five deputy prime ministers, Jamel Saleem al-Arayed, who also advises the prime minister on legal affairs. He wrote that all payments made by Mr Dahdaleh in connection with Alba were known about by its board. The letter was read out during cross-examination of Sasi Mallela, an SFO lawyer. The jury had already heard testimony by Mahmood al-Kooheji, Alba's chairman, that Qays Zu'Bi, Mr Dahdaleh's Bahraini lawyer, suggested during a Manama meeting attended by two other of Bahrain's deputy prime ministers just days before Mr Dahdaleh's first trial was scheduled to start in Aprilthat Bahrain could intervene to stop the trial, as Saudi Arabia had done in the SFO's investigation of alleged bribery by BAE Systems. The SFO alleged in court that Mr Zu'Bi, who did not attend the trial, said that if Bahrain intervened, Mr Dahdaleh would get off and "go after" anyone who testified against him.