The London Ambulance Service has declared a significant incident after three buses collided in Parliament Square this afternoon.
A number of injuries have been reported and the collision has brought the area to a standstill.
"Multiple resources" from the London Ambulance Service responded to the incident, which appears to have taken place near to some roadworks.
Crews were treating "several patients" on the scene, according to emerging planning and resilience officers of LAS. London Fire Brigade is also on the scene.
3 x buses have been in collision. Crews are treating several patients and we have declared a Significant Incident.— LAS Resilience Team (@LAS_TacAdvisor) January 11, 2016
Twitter users posted images showing the extent of the damage caused to vehicles, and the impact it was having on the roads. A number of people have reportedly been injured, although it is too early to say how seriously any of those injuries are.
Parliament square now. Bus crash. pic.twitter.com/nxFdeGIdp4— Liam (@liamdeacon) January 11, 2016
Bus crash on Parliament Square pic.twitter.com/M85CUF0ne1— Chris Follows (@chrisfollowsart) January 11, 2016
Broad Sanctuary was blocked in both directions initially, but has since reopened westbound from Parliament Square, Transport for London said. The eastbound route is shut and delays are expected.