Children have been left disappointed in the run-up to Christmas after letters from Santa arrived at their homes -- in opened envelopes with a gift of chocolate coins missing.

Royal Mail denied Santa's post had been targeted by thieves and put the problem down to its sorting machines, which could not cope with lumpy letters.

It blamed the Oxford Mail, which has been helping Santa send the letters, for posting the envelopes with coins inside.

But it is the first time the Oxford Mail has received any complaints about envelopes arriving open or missing chocolate since it started its partnership with Santa in 1999.

With a fortnight to go until Christmas, its promotions team has received eight complaints from parents and grandparents about envelopes arriving with one end sliced open.

In each case, a letter and card from Santa arrived intact, but all three chocolate coins were missing.

More than 1,200 letters have been sent out so far, each stamped with a message reading: "From Santa, North Pole, Christmas 2004."

Pat Renehan and his wife Carol, of Littlemore, Oxford, ordered six of the £2.99 letters for their grandchildren, who live elsewhere in Oxford.

The letters were sent out from the North Pole via the Oxford Mail's offices in Osney Mead, Oxford, two weeks ago, but only four arrived. One was open, with the coins missing.

Mr Renehan said: "It makes you think perhaps someone felt the coins and thought it might have been money." But Royal Mail spokesman Dan Panes said it was unfair to suggest thieves were to blame.

He said Royal Mail made it clear that coins or objects that might stick out should not be sent in normal envelopes in case they got caught in sorting machines.

Oxford Mail newspaper sales manager Margaret Marsh said the coins were wrapped inside the letters, which were put inside a Christmas card.

She said: "We feel the coins were appropriately packaged in a way that ensured there were no lumps."