35 to 40 times regulatory levels according to investigators at West Virginia University and the California Air Resources Board. About 482,000 vehicles are under the recall order, a potential $18 billion ($37,500 per violation) in fines are pending, and news accounts speculate a criminal indictment for the deception is certain. The VW Group CEO, Martin Winterkorn, said he was "deeply sorry" and ordered an external investigation. The software code was only revealed when the EPA refused to certify VW's 2016 models for sale in the US unless the corporation provided full disclosure. On Sunday, 20 September 2015, VW Group announced it was halting the sale of its four-cylinder diesel models in the US. The US EPA press release on its Notice of Violation, and the California Air Resources Board letter dated 18 September 2015 contain significant chronological detail of the agencies interaction with VW on the issue. On 22 September 2015, VW AG admitted that 11 million cars worldwide had been fitted with software intended to deceive emissions testing. The company issued a profit warning, saying it had set aside $7 billion to fix the fraud. On 23 September 2015, Martin Winterkorn announced his resignation from the CEO position after a crisis meeting of the company board. On 25 September 2015 Matthias Müller was named CEO. Müller was the head of the Porsche marque within the VW corporate umbrella. On 21 April 2017, a U.S. federal judge ordered Volkswagen "to pay a $2.8 billion criminal fine for rigging diesel-powered vehicles to cheat on government emissions tests". The "unprecedented" plea deal formalized a punishment that Volkswagen AG agreed to earlier in 2017. In addition, the plea deal includes a $1.5 billion settlement for various environmental, customs and financial violations. Overall, Volkswagen will pay more than $30 billion in penalties and lawsuit settlements related to the scandal. Electrification strategy 2025 In 2016, Volkswagen Group announced a corporate "Strategy 2025" that focuses on electrification of its portfolio. The VW Group developed the Volkswagen Group MEB platform chassis that will be utilized in a range of various cars and light utility vehicles across several VW Group marques due to its flexibility and floor-mounted battery. As of May 2018, the VW Group has committed $48 billion in car battery supplies and plans to outfit 16 factories to build electric cars by the end of 2022. According to VW Group CEO Dr. Herbert Diess, the company