Two boys have been charged after allegedly stabbing a man and assaulting his son during an attempted supermarket robbery.

The boys, aged 14 and 15, allegedly tried to steal from the supermarket on Kathleen St, northeast NSW’s Tamworth on Tuesday night.

After being confronted by a 51-year-old man, they reportedly left the store briefly but returned shortly after with a group.

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Four teenagers then allegedly attacked the man, stabbing him before his 27-year-old son stepped in to help.

The group fled before police arrived around 7pm.

The 51-year-old man was treated at the scene by paramedics before being taken to Tamworth Hospital with a stab wound to his lower back, as well as cuts and bruises.

His 27-year-old son suffered bruises and abrasions but did not need hospital treatment.

The two boys were arrested just before 8pm and have been charged with assault occasioning actual bodily harm in company, and affray.

They’ve been granted conditional bail and are due to appear in a children’s court on July 8.