POLICE are looking for a "Good Samaritan" who tracked down and detained a suspected teenage mugger.

The man who was driving a white pick-up went to the aid of a group of builders who had chased the 18-year-old, after a woman walking with her two daughters was robbed in Nelson Terrace, Stockton, at 2.30pm on Thursday.

When she tried to hang on to her bag the robber bit her hand leaving a deep wound. During the struggle she grabbed his shirt, tearing it from his back, and he ran off bare-chested down Bright Street, Russell Street and Hartington Road.

Detective Sergeant Jason Hogg said several people gave chase, but it was a man in a white pick-up who caught him.

He said: "We would like to speak to him and anyone else who witnessed the attack, including a member of the public who gave the victim a piece of paper containing the name of the attacker.

"This was a vicious attack. The lady who is in her thirties was with her nine-year-old daughter and teenage daughter with learning difficulties. All three have been left extremely distressed by the incident."

An 18-year-old was in custody at Stockton police station yesterday.