The Serious Fraud Office (SFO) has launched a criminal inquiry into the alleged rigging of foreign exchange (forex) markets.
The government department, responsible for investigating and prosecuting serious and complex fraud, will consider whether traders benefited from the manipulation of benchmark forex prices.
It comes amid an existing probe by Britain's financial watchdog, The Financial Conduct Authority (FCA), which in October joined other regulators around the world, investigating firms over the potential manipulation of the £3 trillion-a-day forex market - the global market for the trading of currencies.
The Serious Fraud Office said it has opened a criminal investigation into allegations of fraudulent conduct in the foreign exchange market, the Press Association have reported.
The Serious Fraud Office has confirmed it has opened a criminal investigation into the commercial practices of GSK and its subsidiaries.
It appealed for whistelblowers from the company to help them with their inquiries.
Whistleblowers are valuable sources of information to the SFO in its cases.
We welcome approaches from anyone with inside information on all our cases including this one - we can be contacted through our secure and confidential reporting channel, which can be accessed via the SFO website.
The scandal is the latest in a number of corruption probes in Iraq, Poland and China against the company.
Anyone with any information can contact the Serious Fraud Office confidentially through their website.
Drugs giant GlaxoSmithKline said it intends to co-operate fully with the criminal investigation into its operations by the Serious Fraud Office. In a statement, the company said:
GSK is committed to operating its business to the highest ethical standards and will continue to co-operate fully with the SFO.
Pharmaceutical giant GlaxoSmithKline is under criminal investigation here in the UK, the company said.
The London-based multinational corporation said the Serious Fraud Office has opened a "formal criminal investigation".
The company is facing similar investigations in Iraq and China.
A criminal investigation has been opened into government electronic tagging contracts held with Serco, as well as G4S, the Serious Fraud Office (SFO) said.
An audit by accountancy firm PricewaterhouseCoopers, launched in May, alleged that overcharging began at least as far back as the start of the current contracts in 2005 but could have dated back to 1999.
Justice Secretary Chris Grayling told the two firms that an independent forensic audit was required to look at internal email trails between executives to establish what happened. While Serco agreed to take part, G4S refused.
Serco allowed a further forensic audit to take place but G4S refused to co-operate and were reported to the SFO.
A criminal investigation has been launched into a contract between security firm G4S and the Government for tagging criminals.
An inquiry has been opened by the Serious Fraud Office after it emerged G4S, along with Serco, had charged the Ministry of Justice for monitoring offenders who were dead, back in prison, had their tags removed, left the country or never been tagged in the first place.
An audit by accountancy firm PricewaterhouseCoopers, launched in May, alleged that overcharging began at least as far back as the start of the current contracts in 2005.
The Government reported G4S in July when the FTSE 100 firm refused to take part in an additional audit to rule out any dishonesty.
The Serious Fraud Office (SFO) has opened an investigation into the Government's contract with G4S for the provision of electronic monitoring, or tagging, services, the security firm has confirmed.
The documents that the Serious Fraud Office (SFO) sent to the wrong person are linked to an investigation into the defence giant BAE Systems.
While it is not clear what the documents relate to, the SFO has investigated the company over contracts it won with several countries including Saudi Arabia, Tanzania and South Africa.
BAE Systems was fined $400 million (£257m) by the US and Britain in 2010 following long-running corruption probes into defence deals around the world.
Last year, the company paid £30 million to the Tanzanian population after failing to keep adequate records of payments it made to receive a defence contract in the country.