London midday: Stocks tumble as jitters grip markets

London's leading share index has given up a short-lived rally and is posting triple-digit losses as nerves over the global economic situation grip the markets again.Mining giants such as Rio Tinto and ENRC are out of favour, though precious metal miners such as Randgold Resources and Fresnillo are wanted again. Banks RBS and Lloyds are also on the rise, partially recovering from heavy losses last week.The European Central Bank has pledged to support bond markets in Spain and Italy by buying the nations' bonds. The G7 group of industrialised nations has also sought to reassure markets, saying it was ready to take action if necessary.Premier Foods is posting a double digit percentage recovery today after sliding on Friday following a sharp drop in profits at the Hovis bread group.In company news, data centre operator Telecity is lower after saying it saw half-year earnings before interest, tax, depreciation and amortisation (EBITDA) rise 30.5% to £49.45m from £37.89m last year, while the EBITDA margin improved to 44.4% from 40.4%. Aerospace group Hampson Industries falls back said volatile conditions within the aerospace tooling market remain with Odyssey in particular facing short term revenue, operational and timing challenges. Results at its Odyssey and GTS tooling businesses for the half of the year and the full year will be lower than initially forecast as the results from cost cuts take longer than expected, it warned. Among smaller companies, Stilo International, a provider of systems that convert text between different computer packages, has won an order for its "cloud content conversion service" with the US IT giant Cisco. Stilo will convert 20,000 of pages in Adobe format into the DITA (Darwin Information Typing Framemaker) standard, using its Migrate service. FTSE 100 - RisersLloyds Banking Group (LLOY) 34.00p +3.52%Randgold Resources Ltd. (RRS) 5,860.00p +2.45%Standard Life (SL.) 176.80p +2.26%Legal & General Group (LGEN) 95.90p +1.16%Severn Trent (SVT) 1,444.00p +0.77%Aviva (AV.) 342.30p +0.68%Old Mutual (OML) 111.60p +0.63%Tesco (TSCO) 364.40p +0.55%Tate & Lyle (TATE) 548.50p +0.18%ICAP (IAP) 402.10p +0.10%FTSE 100 - FallersWeir Group (WEIR) 1,602.00p -7.45%Petrofac Ltd. (PFC) 1,138.00p -5.95%Xstrata (XTA) 988.50p -5.90%Kazakhmys (KAZ) 1,002.00p -5.83%ARM Holdings (ARM) 477.50p -5.63%Eurasian Natural Resources Corp. (ENRC) 597.50p -5.61%GKN (GKN) 183.80p -5.60%Essar Energy (ESSR) 289.00p -5.03%Vedanta Resources (VED) 1,353.00p -4.65%Johnson Matthey (JMAT) 1,687.00p -4.53%FTSE 250 - RisersPremier Foods (PFD) 14.17p +9.34%Home Retail Group (HOME) 125.60p +4.84%BBA Aviation (BBA) 183.50p +3.44%Betfair Group (BET) 586.00p +2.63%COLT Group SA (COLT) 117.80p +1.99%IG Group Holdings (IGG) 412.20p +1.95%F&C Commercial Property Trust Ltd. (FCPT) 94.30p +1.84%PZ Cussons (PZC) 355.00p +1.66%Fidessa Group (FDSA) 1,688.00p +0.96%Cable & Wireless Communications (CWC) 32.25p +0.94%FTSE 250 - FallersLamprell (LAM) 288.60p -13.07%Kenmare Resources (KMR) 37.60p -11.53%Afren (AFR) 94.75p -10.19%New World Resources A Shares (NWR) 571.50p -9.50%Salamander Energy (SMDR) 243.20p -8.98%Renishaw (RSW) 1,283.00p -8.62%Spirit Pub Company (SPRT) 38.50p -8.33%Ferrexpo (FXPO) 358.30p -8.32%Unite Group (UTG) 168.60p -8.12%ITE Group (ITE) 172.80p -7.54%