A young man has been arrested over the death of a four-week-old baby two years ago.

The boy was first taken to Wagga Wagga Base Hospital in NSW on July 27, 2023 in a critical condition.

The baby suffered a number of “unexplained serious physical injuries”, NSW Police said.

Know the news with the 7NEWS app: Download today

Shortly after, the baby was transferred to Sydney Children’s Hospital where he died three days later.

Police investigated the baby’s death, which they deemed suspicious, and on Friday morning arrested a man in Albury.

The 26-year-old is known to the child but the exact nature of their relationship is unclear.

He has been taken to Albury Police Station.

Anyone with any information about the incident is urged to contact Crime Stoppers.