Sample analysis revealed a very low proportion of pork, or less than 0.1 per cent, the Swiss Central Islamic Council (CCIS) said in a statement.

Islamic tradition forbids the consumption of pork.

According to The Local, the group said it believes the traces of pork are the unintentional result of gaps in the production process, saying equipment used to handle the meat may have been used to also manufacture the kebabs.

CCIS staff were shocked by the discovery from random tests carried out in Basel, Biel, Geneva, Kreuzlingen, Lausanne, Lucerne, Winterhur and Zurich.

The organization ordered the test sampling after being "alarmed by the scandal that recently erupted in Germany where 7 per cent of pork meat was found in meat for kebabs."