A manhunt is underway after a man was set on fire in what police have described as a ‘vicious and deliberate’ attack.

Emergency services were called to an apartment block on Todd Street in Warrawong, about 90 minutes south of Sydney, after reports of a fire about 9pm on Monday. 

Police were told the man, 25, had been set alight by a person known to him, and suffered severe burns to half of his body, including his upper torso and legs.

The victim was treated by paramedics at the scene and was airlifted to the Royal North Shore Hospital where he remains in a critical condition.

NSW Police Detective Chief Inspector Brad Ainsworth said the attack was ‘targeted’.

‘We are waiting until he (victim) can talk to us and hopefully then he will have some valuable information that will lead to the identification of the offender,’ he said. 

‘I would think people in that unit block at Warrawong would know more so I encourage the residents there to come forward and help us out with our investigation.’ 

A crime scene has been set up and an investigation launched. 

Anyone with information has been urged to come forward.  

Emergency services were called to an apartment block on Todd Street in Warrawong, about 90 minutes south of Sydney , after reports of a fire about 9pm on Monday