AS THE envelopes came through the door and thudded on to his doormat, Peter Sutton was bemused.

That became bewilderment as he saw that every one of the 62 letters delivered at the same time had come from British Gas.

Yet his amazement gave way to complete astonishment when he saw they were bills – and the total debt he owed was less than £30.

The bills dated back to 2007 but were demanding a grand total of just £28.57, only a few pounds more than it cost to post the huge amount of letters.

Now British Gas has launched an investigation into how the blunder happened.

Mr Sutton, 87, who is retired and lives in Eastleigh, said: “I was absolutely staggered and I cannot believe they would send me this many bills.

“It took me more than an hour to open them all. I thought is was bizarre at first and I was a bit apprehensive to open them.

“The postman was very surprised and had to wrap them all up in an elastic band.”

The gas bills were for three properties in Southampton of which Mr Sutton is the landlord.

In the past British Gas has billed Mr Sutton by estimating the amount used, but he now believes they have begun reading his meter causing them to send him a wave of revised gas bills dating back eight years.

Grandfather Mr Sutton said: “As I went through them I saw a figure for more than £5,000 that was credit for my account and I thought I had won the lottery because there was thousands of pounds in credit. But it seems that this has been dealt with over the years.

“I hope from now on they are going to actually go into the property and read the meter whereas before they have just been estimating.”

To send Mr Sutton the 62 second class letters, British Gas would have had to pay at least 36 pence per letter, costing a total of £22.32.

That means they would have made just £7.25 from Mr Sutton’s debt of £28.57.

He added: “I have always been a British Gas customer and use them for my heating and electricity as well.

“I am disappointed if this is the way that British Gas handle it and because they also handle my electricity bill. I will have to see if they send me the same amount of postage.”

Leigh Franks, of British Gas Business, said: “I am sorry that we sent a large number of letters to Mr Sutton, we have made sure that no more correspondence will be sent.

“We are looking into how this happened as a priority and will contact Mr Sutton to apologies and explain.”