An 18-year-old man is in custody following a serious assault on Cashel Street last night. 

The teenager assaulted the victim around 6:20pm in Cashel Mall.

The victim sustained serious injuries to his head.

A police spokeswoman told Chris Lynch the victim was transported to hospital and remains in a critical condition. 

It’s understood a group of youths chased the man before the assault took place.

The police spokeswoman said police wanted to thank the members of the public who assisted them with their enquiries and helped hold someone accountable for their actions. 

The man is due to appear in the Christchurch District Court late Wednesday on a charge of wounding with intent to do grievous bodily harm.