The City of London Police have arrested two men on suspicion of fraud as part of its investigation into the horse meat scandal.

The men have been held on suspicion of conspiracy to defraud and the police have interviewed a further two men under caution, Sky News reported.

Few further details have been released, including the men’s nationalities, about the investigation it launched in May in conjunction with the Food Standards Agency.

Detective chief superintendent Oliver Shaw said: “This is an extremely complex investigation covering a number of jurisdictions and a variety of businesses.

“We are working closely with police forces, other law enforcement agencies and regulators to determine whether horse meat being used in a range of meat products was deliberate and coordinated criminal activity.”

Last month MPs in the Commons Environment, Food and Rural Affairs Committee, condemned the slow pace of the investigation.

The horse meat scandal first erupted in January and since then retailers including Asda, Tesco, Iceland and Aldi discovered horse DNA in frozen burgers.