A flasher exposing himself and indecently assaulting women in Christchurch's earthquake-ravaged "red zone" is being pursued by police. 

Police are asking members of the public out in the early hours of the River-Retreat Rds area of the eastern suburbs to "remain aware of their surroundings". 

"A small number of reports have been received of a young male approaching women, exposing himself, and in some instances indecently assaulting them," a police statement says this morning. 

"These have mainly been in the early morning, between 6.30am to 8am, and the latest report was on New Year's Day." 

If anyone has any information on these incidents that could help officers, they are asked to contact police on 105 and quote file number 220101/8979.