Sweett Group lost more than a quarter of its value yesterday, as a new inquiry into bribery claims on a $100m (£65m) hospital project in Morocco investigates "material instances of deception".
Sweett Group, which was managing the hospital's construction, hired the law firm Pinsent Masons last year to investigate claims it had paid a bribe to an official in the United Arab Emirates president's personal foundation to land the deal.
The company closed the original investigation in January with the allegations "unproven". It appointed a second law firm, Mayer Brown, to carry out another inquiry and said yesterday: "Evidence suggests material instances of deception may have been perpetrated by a former employee or employees. Sweett soured 14.5p to 36.5p.
Miners added 5.93 points to the benchmark FTSE 100 index after operators with exposure to Chile reassured investors that the 8.2 magnitude earthquake that struck the country had not affected mines there. But companies going ex-dividend pegged back the FTSE 100, with Resolution, off 15.3p at 288.4p, and Pearson, down 30p to 1,014p, the biggest fallers.
The FTSE 100 inched 6.43 points higher to 6,659.04, a three-week high.
Marks & Spencer made gains after analysts and investors gave its overseas expansion plans the thumbs up, helping it to climb 10.1p to 469.9p.
Office2Office was downbeat on the year ahead, as it reported on its 2013 performance. The office services specialist, which is facing a shareholder rebellion, swung to a profit of £1.8m in 2013, from a loss of £1.6m. But its chairman, Jim Cohen, warned that the tough market meant the company expects profit this year to fall short of 2013 performance. Office2Office dropped 0.5p to 22p.
The online payment processor SafeCharge got off to a good start on Aim yesterday. The company, whose main clients include William Hill and Gala Coral, closed 7.5p above its 162p float price.
The Aim-listed gold explorer Alecto Minerals added 0.1p to 1.27p after upping the estimate for gold deposits at its flagship Kossanto gold project in Mali by a hefty 80 per cent.