Peter Catchpole was surprised when the uniformed officer, in a marked car, said he could not take any action to stop the thieves.

Instead of springing into action, the policeman remained in his car, taking some details, and only went to inspect the scene after the thieves had gone.

Mr Catchpole saw the group of men throwing lead off the roof of a flat in Croydon, South East London, into a trolley near some garages in an alley.

He spotted a police patrol car just yards from the thieves and told him about the theft, expecting the officer to go and confront the men.

Mr Catchpole said: "He was not doing anything. I told him people were stealing lead and he said next time I should dial 999 and call the police. I said 'but you are the police'. I could not believe it.

"It was quite surreal. By the time other policemen could get here, they would have been gone.

"This guy could not have been closer. One of the three thieves even walked past his car and got a drink from the local shop.

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