Tube rush hour chaos

London Underground has begun an investigation after a broken-down train incident led to morning rush-hour travel chaos for thousands.

An early-morning Victoria Tube line train lost power after hitting an object on a section of track where maintenance had been taking place overnight.

The stalled train, which was able to get into Seven Sisters station in north London, caused a shut-down of the entire Victoria line.

The line, running from Walthamstow in east London through the heart of the capital to Brixton in south London, includes Victoria, which is the busiest of the Underground stations.

An LU spokeswoman said: "At first we were running a two-train shuttle between Brixton and Seven Sisters, but this was insufficient to cope with the numbers as the morning peak progressed and we had to shut the whole line down.

"There had been some engineering work going on in the area and there will be a very thorough investigation into this incident."

The train stalled at about 5.20am and the entire line was out of action from 6.34am. Services were expected to resume at about 9am.

To add to the problems for passengers, a signal failure at Gunnersbury station in west London led to morning rush-hour delays on the District line.