Transport for London has said it is dealing with a cyber-attack. The organisation, which runs most of London’s transport network, said it had undertaken immediate action to prevent any further access to its systems and was working closely with the relevant government agencies, including the National Crime Agency and the National Cyber Security Centre. TfL said it had found no evidence that any customer data had been compromised, and that there was no impact on its transport services. Shashi Verma, TfL’s chief technology officer, said: “We have introduced a number of measures to our internal systems to deal with an ongoing cybersecurity incident. The security of our systems and customer data is very important to us and we will continue to assess the situation throughout and after the incident. “Although we’ll need to complete our full assessment, at present there is currently no evidence that any customer data has been compromised. There is currently no impact to TfL services and we are working closely with the National Crime Agency and the National Cyber Security Centre to respond to the incident.” A NCSC spokesperson said: “We are working with Transport for London, alongside law enforcement partners, to fully understand the impact of an incident.” Sources told the BBC that the backroom systems at TfL’s corporate headquarters were mainly affected and staff had been asked to work from home if possible.