A man has been charged with aggravated animal cruelty offences after allegedly killing nine puppies that had been advertised for sale online.

The 25-year-old man was arrested at a home in Kurri Kurri, about 35 kilometres north-west of Newcastle, on Thursday night and is due to face court on Friday following the deaths of the bull terrier cross puppies, which were believed to have been aged between six and eight weeks.

Lucky with veterinarian Julian Suchowersky at the RSPCA veterinary clinic in Rutherford, near to Newcastle. Credit:Peter Stoop

Police will allege that the owner of the 11 tan and white puppies had placed an online advertisement offering the animals for sale on March 5.

When the puppies had not sold nearly a week later, the owner offered the puppies free of charge to the 25-year-old, who allegedly collected them about 4.30pm on Wednesday.