Iran has deployed hundreds of police across Tehran ahead of the beginning of Persian New Year celebrations. Authorities fear the occasion will be used by opposition supporters to protest against last year's disputed presidential election results. Tehran's police chief Gen Hossein Sajedinia told reporters that police were out in force to prevent any event happening in the city. The authorities have branded the ancient festival is 'un-Islamic'. Opposition leaders called for supporters not to use the New Year festivities to protest, and said people should avoid provoking the authorities. The festival, called Chahar-Shanbe Suri, celebrates the coming of spring and dates back to Zoroastrian Persia, before Islam.