Transport for London (TfL) has restricted its online services due to an ongoing cyber attack.

The organisation, which is responsible for most of London’s transport network, said it is preventing passengers from viewing their journey history for trips paid for by contactless cards.

It has also limited access to some live travel information services via apps and its own website.

This includes train updates and TfL JamCams, which usually show live feeds of traffic on major roads.

In addition, TfL has restricted access to the photocard portal – which allows customers to apply for travel concessions.

The booking system for the Dial a Ride door-to-door minibus service was made unavailable earlier this week.

TfL said essential bookings can now be made by phone and it is hoping to return to a full service “in the coming days”.

Shashi Verma, TfL’s chief technology officer, said: “The security of our systems and customer data is very important to us.

“We continually monitor who is accessing our systems to ensure only those authorised can gain access.

“We identified some suspicious activity on Sunday and took action to limit access.

“A thorough investigation is currently taking place and we are working closely with the National Crime Agency and the National Cyber Security Centre to respond to the incident.

“Internal measures to limit access remain in place and there remains no impact to our public transport services and no evidence that any customer data has been compromised.

“We will continue to keep our customers and our staff updated on the incident as part of this ongoing work and thank them for their patience as we respond to this incident.”