A landslide on a major rail route into London was caused by tree removal as well as torrential rain on the morning of the incident, according to one commuter.

The Bushey resident, who asked not to be named, regularly travels on the ill-fated route to Euston where two trains collided following the landslip near Watford Junction on Friday morning.

READ MORE: Hundreds rescued after train derails at Hunton Bridge, near Watford Junction.

She said mass deforestation carried out along the line by Network Rail, combined with heavy downpours on the morning in question, had unsettled the earth and made future landslides more likely.

“This has moved from me being upset at wanton destruction to the company now endangering the lives of passengers and their employees,” she said.

“The evidence is of a huge amount of tree cutting - it is no exaggeration to talk of the destruction of tens of thousands of trees – is all along the line and can be seen from roads in the area.

“As a country prone to the storms we saw at the end of last week, why are we taking down trees?

“Network Rail will tell you that it is necessary to prevent leaves on the line. They will also say that branches on the line cause delays and are dangerous.

"They are but the extensive, efficient rail network in Europe manages very well with trees everywhere. They manage their trees.”

Trees are widely believed to prevent soil erosion, protecting earth from the impact of rain and binding soil, particularly on sloping land, with their roots.

However a tweet sent by Network Rail on the morning of the landslide confirmed that the area had been subject to tree clearance in the last six months “to help to stabilise the embankment”.

It continued: “Contrary to popular belief, trees on steep embankments can actually cause or exacerbate landslips, and work was continuing to net the embankments to make them safer still.”

Network Rail spokesman Jon Crampton said: “Torrential downpours appear to have caused a flash flood which washed the embankment onto the railway below. Ongoing maintenance work has seen planned vegetation removal at this location to help stabilise the embankment, along with netting to make it even safer.

“A full investigation into this incident will take place to establish the facts.”