Why did Oliver run out of the room crying "Help, help!"?

Oliver cried for help when he was running an errand for Mr. Brownlow, and he was abducted by Bill Sikes and Nancy.

'You see he knows me!' cried Nancy, appealing to the bystanders. 'He can't help himself. Make him come home, there's good people, or he'll kill his dear mother and father, and break my heart!'
'What the devil's this?' said a man, bursting out of a beer-shop, with a white dog at his heels; 'young Oliver! Come home to your poor mother, you young dog! Come home directly.'
'I don't belong to them. I don't know them. Help! help!' cried Oliver, struggling in the man's powerful grasp.
'Help!' repeated the man. 'Yes; I'll help you, you young rascal!