Leading security firm Armaguard has been hit by allegations two of its Melbourne officers stole almost $500,000 while on suburban cash runs.

Mustafa Yorus, 44, and Celalettin Karaca, 25, have been charged with stealing the money as they took big cash sums to and from automatic teller machines.

Moonee Valley CIU detectives arrested the pair last week.

They raided properties at Mickleham and Dallas in Melbourne’s northern suburbs.

A Victoria Police statement said it was alleged that there were more than 10 instances where irregularities had emerged after cash runs.

The runs were to machines in Melbourne, Tarneit, Keilor Downs, Delahey, Craigieburn, Sandringham, South Melbourne, Clifton Hill, Essendon, Pascoe Vale and Mill Park.

Mr Yorus and Mr Karaca have been charged with 11 counts of theft.

The statement did not say whether the money had been recovered.

Sources said there was puzzlement about how money could be stolen, given the level of CCTV scrutiny on staff while they do such work.

The alleged theft would be the biggest in the sector for some years.

Armaguard is part of the Linfox group of companies and is the nation’s cash transport security firm.

It provides services for the big banks and major retailers.

Linfox was contacted for comment on how much of the money had been recovered and whether clients were protected from loss.

The company did not respond.