G4S shares slump by nearly 10% after Olympic security furore The army has been drafted in to assist with security operations during the Olympics after G4S failed to provide 10,400 security guards. Photograph: Leon Neal/AFP/Getty Images Shares in G4S slumped by nearly 10% on Monday morning in the wake of the furore over the company's admission that it cannot provide enough security guards for the Olympics. Investors in the security company saw the stock take a pounding following the revelation that its recruitment programme has fallen short, forcing the army to step in. G4S shares fell 9.83% in the first half hour of trading, shedding 27p to 251.6p as one City analyst predicted that the company's chief executive will "fall on the sword" along with a slew of senior colleagues. The army will provide at least 3,500 soldiers to cover the shortfall on a £284m contract that saw G4S agree to provide 10,400 security guards. G4S now faces a loss of up to £50m on the contract. In an interview with the Daily Telegraph on Monday morning the G4S chief executive, Nick Buckles, said he expected the company's share price to suffer, while admitting doubts over his own future. The share price is going to move on Monday, it just depends how much. I have been here 27 years. I am very committed to staying. It just depends, doesn't it? Investment bank UBS gave a further indication of investor sentiment this morning by downgrading its rating on G4S from a "buy" to "neutral." The Olympics misfire adds to a troubled 12 months for the company, which had to abandon a £5.2bn takeover of Danish rival ISS in the wake of a shareholder revolt. Seymour Pierce also reduced G4S from a "buy" to a "hold" this morning as it predicted a wave of executive departures, led by Buckles, who will be grilled on Tuesday by MPs on the House of Commons home affairs committee. Kevin Lapwood, a Seymour Pierce analyst, said the UK government was a vital customer for G4S, with the UK providing just under 20% of group revenues - £1.2bn - and around half of that coming from the government. It appears certain that CEO Nick Buckles, who is due to appear before MPs on Tuesday, will fall on the sword along with other senior UK management. This could lead to a period of instability at the company which appointed a new Chairman just over a month ago. Whoever is in charge will have a lot of work to do to repair the company's reputation, especially at home in the UK and with the UK government, its single largest customer. This will be crucial for the company's future," said Lapwood.