Some of the world’s leading chocolate manufacturers could face tough fines after German authorities raided seven companies in a price-fixing investigation.

The German Federal Cartel Office raided seven companies, including Nestle, Mars, Kraft and Ritter, last Thursday after “information from the market”.

A spokeswoman for the authority said: “We think there was collusion on price rises.”

The raids follow recent price rises of between 10 per cent and 12 per cent that were made by the companies within a few weeks of each other.

The manufacturers blamed increases in the price of cocoa and nuts for the price rises.

The Federal Cartel Office has the power to fine companies up to 10 per cent of their turnover.

The spokeswoman said that this potentially could be 10 per cent of world sales because the parent company is deemed responsible for the actions of its subsidiaries.

The authority’s investigation is expected to take several months.

It is about to receive documents from all the companies.

Nestlé, Mars, Kraft and Ritter have confirmed that their German offices had been raided and said that they were co-operating with the investigation.

Other companies have been sent letters by the Federal Cartel Office telling them that they are part of an industry-wide investigation.

A spokesman for Nestlé said: “We can confirm the visit, but are unable to offer any further comments on the proceedings.”

In the first six months of last year the sales of Nestlé, which makes KitKat, Aero and Yorkie bars, were SwFr51.1 billion (£24 billion).

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