Seven people were injured in the incident

Harry Anscombe arrived at Camden Town station just after the accident on the northbound Northern Line.

Seven people were injured in the accident, but many, many more were affected, he said.

"There were lots of people who were shocked, but there were lots who were very angry also.

"People seemed really quite fed up and angry about what happened. Camden is a very old station and it's always very busy, especially on the Bank branch."

Mr Anscombe, who was planning to take the Tube to meet friends for lunch, described the scene when he arrived: "There were fire engines arriving, lots of noise and confusion.

There were lots of blackened faces, there was one man I saw with bandages on his face with blood streaming down Eyewitness Harry Anscombe

"They had stopped the escalator and the ambulance men and firemen were ushering the passengers up from the tunnel.

"There were lots of blackened faces. There was one man I saw with bandages on his face with blood streaming down.

"They put out chairs at the top of the escalator and were sitting people down."

Poor visibility

Mr Anscombe asked one of the passengers what had happened, but the man said he did not know because it was "so black down there".

The passenger said the derailment had caused a huge amount of dust to fly up, making it difficult to see.

Mr Anscombe praised the emergency services, who he said seemed to have the situation well organised.

"They were being really good, and the underground people came out as soon as they could to tell people where to take alternative routes, but it shouldn't have happened in the first place."