The London stock market tumbled more than two percent in early deals on Tuesday, with banking shares sinking amid fears for the eurozone debt crisis, traders said. The benchmark FTSE 100 index was down 2.12 percent at 5,802.42 points shortly before 0800 GMT. Lloyds Banking Group shares dived 4.20 percent, Royal Bank of Scotland shed 3.56 percent and Barclays lost 3.83 percent.