LONDON -- British parliamentarians are Watch Sexy urban legends season 1 episode 8well-known for fighting like cats and dogs.

But lately there's been some pretty serious cat-on-cat violence at 10 Downing Street, and we're not talking about intra-party disagreements between MPs.

Photojournalist Steve Back is a freelance press photographer dedicated to documenting the comings and goings at the residence of the prime minister, largely via his Twitter account, @PoliticalPictures.

Recently, Back has brought attention to the ongoing battle between Larry the Cat, chief mouser at 10 Downing Street, and Palmerston, Larry's counterpart at the Foreign & Commonwealth Office (FCO) at Whitehall, London.

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Larry came to 10 Downing Street during David Cameron's tenure to take care of rodents/as a public relations gimmick, but following the political turmoil of the past few weeks, his position had been precarious. Now, Larry appears to be facing a new threat as Palmerston seems keen to usurp 10 Downing Street territory.

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Back has risked personal injury to document the encounters between these two fiercely territorial felines, sometimes even intervening to end the fighting. Back has expressed outrage over how little is being done to alleviate the situation.

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Treats and armed officers have both been called in intermittently as a temporary ceasefire, but no adequate long-standing solutions have been proposed.

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The fighting became so intense, Larry had to pay a visit to the vet, allowing the ambitious Palmerston to take temporary control over 10 Downing Street.

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Larry's return and the recent announcement that the Treasury had brought in its own chief mouser have added even greater ambiguity to the turf wars. No news yet on whether Gladstone the cat will choose to remain neutral, form an alliance or lead his own bold campaign to claim the street.

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Back's efforts to draw attention to the fighting have not gone without notice; Battersea Dogs & Cats, the animal shelter from where Larry, Palmerston, and Gladstone have all been adopted, has apparently been in contact to help neutralise this potential tragedy.

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At this point, we can only hope that somehow an im-purr-fect peace will be reached.