DETROIT — General Motors on Friday said it is recalling more than 68,000 Chevrolet Bolt electric vehicles, a month after regulators began investigating whether they were at risk of catching fire.GM said it has identified five Bolt fires — two more than NHTSA cited in opening a preliminary evaluation of the matter. The fires possibly relate to high-voltage batteries produced by LG Chem in South Korea, GM said.The automaker and NHTSA are still working to determine the cause of the issue, but GM pl