Morrison ( LON:MRW ) is the biggest faller, losing about 5.2% though it was not the one with bad news. Tesco 's ( LON:TSCO ) woe shows no signing of abating. Wednesday brought news of a FCA investigation into its accounting scandal - which since it was first unveiled has seen more the £4bn slashed from the supermarket's market value. The regulator has launched a full investigation following the grocer's overstatement of expected profit by £250mln. Tesco said in a stock exchange statement that it will co-operate fully with the authorities. Tesco shares are down 4.45% trading at 178p.