I tried to embed the video but the code from their website is too complicated and doesn't want to work with SMF, so here's a link to the story:
http://news.sky.com/skynews/Home/Strange-News/Rat-Giant-Rodent-Shot-Dead-On-Bradford-Estate-Creature-Could-Be-Descendent-Of-Coypu-Species/Article/201008315696471?f=rss
AH RATS! THAT IS A BIG RAT! Are they sure it is a rat or could it be one those rodents from South America?
The article said they believe they are Coypu, which is a rodent from South America. There are other giant rodents native to South America, such as the Capybara, but they more closely resemble Guinea Pigs than rats.
The Coypu:
(http://www.pacificparanormal.com/forums/index.php?action=dlattach;topic=3097.0;attach=1523)
The Capybara:
(http://www.pacificparanormal.com/forums/index.php?action=dlattach;topic=3097.0;attach=1521)
Coypu were originally brought to the UK and raised for their fur. They escaped and established large breeding colonies in spite of several decades of coordinated extermination efforts. Obviously the eradication efforts were unsuccessful. Here's a study on the history of feral Coypus in the UK.
http://vege1.kan.ynu.ac.jp/isp/pdf/Baker.pdf
You may find the following passage disturbing:
Coypus are native to South America and have been widely farmed for their fur. There have been numerous escapes from captivity and in some countries animals have been deliberately released to try and establish feral populations that could be cropped (Lever 1985). Feral coypus are now found in North America, the Middle East, Africa, Japan, and the Asiatic part of the former Soviet Union. In Europe there are widespread populations and they are particularly common in France, Germany, and Italy (Mitchell-Jones et al. 1999).
So those urban legends about giant rats in the sewers of America's major cities are probably not so far fetched after all. ;D