Security guards group G4S have had to count the cost of last year's Olympics fiasco after seeing annual profits drop by 32% to £175 million.

The company, which is the largest employer on the London Stock Exchange with 620,000 staff in 125 countries, took a hit of £91 million on the Games project after it failed to provide all of its 10,400 contracted guards.

Stripping out the contract blow and restructuring costs of £45 million from more than 1,000 job cuts in developing markets, G4S said its profits rose by 6% to £516 million in the year to December 31.

Its reputation took a hammering after the botched London Olympics contract, when the group only fulfilled 83% of contracted shifts. The fiasco led to the resignation of two senior directors and fuelled fears that G4S may miss out on future Government contracts.

However, chief executive Nick Buckles said the underlying business performed well in 2012, with organic turnover growth of 7% largely due to a number of new North American commercial and UK government contracts.

He added: "Our market leading businesses, broad customer base and £3.5 billion a year contract pipeline give us confidence in the outlook for the group."

Deals included facilities management for the Ministry of Justice at more than 340 court buildings in the Midlands, Wales and the North of England and outsourcing services for Lincolnshire Police in the first contract of its kind to be awarded by a British police authority.

While its UK government businesses performed "extremely strongly" last year, the company said it would be hard to maintain such high growth this year. However, it expects more double-digit growth in developing markets.

G4S shares were 2% lower but have risen 17% in the year to date as the group attempts to draw a line under the Olympics shambles.

Keith Bowman, equity analyst at Hargreaves Lansdown stockbrokers, said: "Significant opportunities to help governments cut costs persist, while the group's track record and diversity should eventually allow it to recover from its own annus horribilis."