The former chief executive and CFO of technical services group Imtech have paid back €1.5m and €700,000 in bonuses following the discovery of major fraud, the company said on Tuesday.

Imtech has been hit by a €150m write-off on an amusement park project in Poland and a €220m write-off on its German activities after fraud was uncovered earlier this year.

The Dutch shareholders’ association VEB had threatened to take legal action against former CEO René van der Bruggen and CFO Boudewijn Gerner for misleading investors.

The VEB said they are responsible for presenting the wrong first-half figures to investors last year. This may have led to investors buying shares in the company based on misleading information.

Imtech also said on Tuesday it had posted a loss of €230m in the first half of this year, compared with a loss of €112.6m in the same period of 2012.

The loss is due to write-offs and the cost of a restructuring process, involving the shedding of 1,300 jobs.