“The San Francisco Municipal Transportation Agency gave customers free rides on its Metro light-rail service all day Saturday, a precaution after an apparent hack of the agency’s computer system.
Pink ‘Out of Service’ messages gleamed from the ticket machines at Powell Street station, where Muni operators had taped paper signs that said ‘Metro free.’
‘We are currently working to resolve the situation,’ said Muni spokesman Paul Rose, who declined to confirm the hack or suggest another reason for the rider windfall. He said the message ‘You hacked’ appeared on Muni agents’ computer screens Friday.”
Source: Free rides for Muni customers after apparent computer hack – SFGate