Syndicated columnist Jack Anderson was struck on the head by a man wielding a pipe or a stick and robbed of about $100 as he left his downtown Washington office Thursday afternoon.

Anderson, who was not available for comment late yesterday, was walking to his car about 4:30 p.m. Thursday from his office near 16th and P streets NW when a man said "Good afternoon," then struck Anderson on the back of the neck, according to a D.C. police report and a spokeswoman for Anderson.

The man then demanded money, and Anderson gave him all the money in his pockets.

The man appeared about to strike Anderson again when he was apparently frightened off by the scream of a woman who had seen the attack from her office in a nearby building, Anderson's spokeswoman said.

The spokeswoman said Anderson believed his assailant was carrying a pipe, but that the witness described the object as a light-colored stick.

After the assault, Anderson returned to his office in the 1500 block of P Street NW, where his spokeswoman called the police.

She said she was placed on hold by the 911 operator for about five minutes, and that police arrived about 15 minutes after she made the report.

A police spokeswoman said a search of the area yielded no suspects.

Anderson was not seriously injured in the incident and worked yesterday as usual.