A Sanctuary Point school was locked down after a construction worker on the premises was stabbed by an intruder. About 10.35am a 40-year-old man was working in a fenced-off area of the school when he noticed a man in the construction zone.The worker approached the man and was stabbed in the arm, police said. The attacker fled the scene. Shoalhaven Police were called and the school was locked down as a precaution.The victim was taken to Shoalhaven Hospital for treatment.The offender is described as being in his late 20s or early 30s, with a slim build and dark complexion. He had a goatee and a moustache. He was wearing baggy torn jeans, a blue-green top and a pair of light-coloured joggers.Anyone with information about the incident or who can assist police in identifying the man is urged to contact Shoalhaven Police via Crime Stoppers on 1800 333 000.