A 38-year-old man has been arrested following an attempted armed robbery in St Albans yesterday.

A 73-year-old St Albans woman was carrying shopping bags along Alfrieda Street when she was approached by a man who made demands for cash about 11.40am.

An unknown male witness attempted to intervene and assist the victim.

It is alleged the offender hit the woman with a metal pole.

A 38-year-old man was arrested today at a St Albans address and is assisting police with their inquiries.

Investigators are keen to speak to the witness.