Nelson police are concerned about easy access to alcohol and have questioned whether parents know what their teenagers are doing after nine teens were arrested following the city's annual Mask Parade on Friday night.

The parade was marred by drunken and disorderly behaviour as between 200 and 300 teenagers gathered around the cathedral steps on Upper Trafalgar St.

Police said those arrested, whose ages ranged from 14 to 18, had been charged with disorder offences.