Germany's leading armoured-truck company, Heros, has collapsed amid the arrest Monday of four senior executives for allegedly helping themselves to some of the cash which it transports and counts for banks and shops, DPA reported. Prosecutors and police in Dusseldorf said 300 million euros (358 million dollars) had gone missing. Four men were remanded in custody on suspicion of serious misappropriation and organized crime. Police searched homes and offices Friday in three German states. Heros has filed for insolvency for all 23 of its business units and the German central bank offered to extend its branch opening hours so that large cash users can obtain banknotes and coins until normal cash transport services resume. An insolvency administrator was expected to decide when the bullet-proof trucks can return to the roads. Police say executives of a Heros business unit, Nordcash, are suspected of diverting cash into their own pockets as well as to finance the business operations of Nordcash. The Heros group does not release sales or earnings figures. It employs about 3,000 guards and clerical staff. Last year the Heros group took over its main German competitor, Securities Deutschland.