A boy has been charged after an alleged armed robbery in Sydney’s South-West earlier this month.

About 7.35pm on Monday 4 July 2016, a 54-year-old woman was behind the counter of a small supermarket on Hillcrest Street when four teenagers entered.

One of the males was allegedly armed with a knife and as they approached the counter they threatened the woman while demanding cash and cigarettes.

The woman handed over a small sum of money and cigarettes and the teens ran from the store.

Police were called and a crime scene has been established while further investigations are carried out by Campsie detectives.

About 12pm today (Friday 22 July 2016), police attended a home on Church Road, Yagoona, and arrested a 16-year-old boy.

He was taken to Bankstown Police Station and charged with robbery whilst armed with an offensive weapon.

He was refused bail to appear at a children’s court tomorrow (Saturday 23 July 2016).

Inquiries to identify the remaining three offenders continue.