A young man is fighting for life after a horror fall at a worksite in Sydney.

The man, aged in his 20s, sustained serious head injuries when he fell a reported 3m at a workplace on Canberra Ave in St Leonards about 9.35am on Wednesday.

Rescue crews used a stretcher to secure the man before an on-site crane was used to lower the stretcher to waiting paramedics, Fire and Rescue NSW Superintendent Adam Dewberry said.

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The man was rushed to hospital in a critical condition.

“Let’s stay safe, everyone,” Dewberry said.

“We want to send everyone home safely. Particularly from your work sites.”

WorkSafe NSW has been contacted for comment.