Britain\'s industrial output slumped 0.7 percent in October from the September level, official data showed on Wednesday, dashing market expectations and sparking concern over the health of the economy. Industrial production sank by 1.7 percent in October on a 12-month comparison, the Office for National Statistics (ONS) also said in a statement. Market expectations had been for a lighter monthly drop of 0.2 percent and a 12-month decline of only 0.7 percent. Manufacturing output, which excludes mining and quarrying, as well as the electricity, gas and water supply sectors, also fell 0.7 percent in October from September, but rose by 0.3 percent on an annual basis, said the ONS. \"UK industrial production numbers are pretty disappointing,\" noted ING economist James Knightley. \"This report increases the probability that we will see a negative GDP (gross domestic product) reading for the fourth quarter of 2011.\" The British economy grew by 0.5 percent in the third quarter, accelerating from 0.1-percent growth in the second quarter of the year. However, economists argue that the outlook remains clouded by the unresolved eurozone sovereign debt crisis, government cutbacks and high inflation.