Ali Ibrahim, 29, was shot outside his home in Christian Road, Punchbowl, in an attack said to be linked to his views on the bloody crackdown in Syria.

Police say he answered a knock at the door about 12.45am yesterday and spoke to at least one man before he was shot and his attackers fled.

His wife and young son and daughter were inside at the time.

He was rushed to hospital and underwent surgery, but there are fears that he may be permanently disabled.

It was the 20th shooting in Sydney since January 1.

Assistant Commissioner Frank Mennilli said Mr Ibrahim could be charged if he was found to have lied to police.

``Once again, we're faced with a victim of a serious crime who says that he does not know who the person is and he has no information that can really assist investigators,'' Mr Mennilli said.

``Yet we have an individual that answers a knock at the door . . . and walks out and opens the door and speaks to this individual.''

Jamal Daoud, of the Social Justice Network refugee support group, who spoke to the family, said Mr Ibrahim had been shot over a heated Facebook debate on his support for the Bashar al-Assad regime in Syria.