Woman set alight while walking in Sydney

The woman was attacked by the man and set alight while walking in Sydney. Photo / Thinkstock

A woman was heard screaming after she was set alight by a man while walking through Sydney.

The 33-year-old was walking along Regent Street in Chippendale about 9.45pm local time last night when a man approached her and set her alight.

"A man followed her down the laneway, chased after her and set her alight. She was screaming, obviously in pain," Acting Inspector Sam Crisafulli told ABC radio on Friday.

He said bystanders had seen the attack and rushed to her aid.

"They heard the noise and came to help.

"They have taken her inside and attempted to extinguish the flames with water."

The woman was rushed inside a nearby business, believed to be a brothel, where an employee extinguished the flames.

Paramedics treated her for severe burns to her upper body, before taking her to Royal Prince Alfred Hospital where she is in a critical but stable condition, Mr Crisafulli said.

Police said they were now looking for a man seen running from the scene into Meagher Street.

He is described as being of medium build and was wearing white joggers, long dark pants and a long sleeved dark hooded jacket.

Anyone with any information should call Redfern Local Area Command or Crime Stoppers on 1800 333 000.

-AAP