Beijing: Over 40 passengers were injured on Tuesday when two subway trains collided in Shanghai, China's commercial centre, following signal system failure.

The accident occurred when one train smashed into the rear of another. Most of the people sustained minor injuries, state news agency reported quoting Shanghai Shentong Metro Group Co.

The crash happened following signal system failure at one station on the Line 10 subway, it said, adding that about 500 passengers have been evacuated from the trains.

This was the second such crash that took place due to faulty signal failure.

About 40 people were killed and over 200 injured when a high speed bullet train crashed into the rear of a stationary train in July this year. Investigations fixed the blamed on faulty signal system which apparently was disrupted by thunder and lightning.