A witness testified yesterday that he dove over a bar to avoid being shot by a gunman who police said killed another bar patron.

District Judge Kim Hoots ordered the suspect, Adriel Russell, 24, of Arlington, to stand trial on homicide charges in the Oct. 19 death of Clayton Thompson, 31, of Brentwood. Investigators said Mr. Thompson was caught in the line of fire when Mr. Russell began shooting at another man.

A witness, who now is in protective custody, testified yesterday at a preliminary hearing that he saw Mr. Russell enter Longo's Bank Cafe on Warrington Avenue, Allentown, and glare at Eric Wormsley, 29, of Beltzhoover. The witness, who was seated nearby at the bar, said Mr. Russell fired at Mr. Wormsley.

Pittsburgh police homicide Detective Joseph Meyers testified that Mr. Russell admitted firing at Mr. Wormsley. The detective said Mr. Russell admitted chasing Mr. Wormsley out of the bar and back inside, then out again and down an alley while firing shots.

Mr. Wormsley eventually ran to an acquaintance's home, where he discovered that he had been wounded. He called 911 to report the incident.

A bullet fragment was surgically removed from Mr. Wormsley's liver, Detective Meyers testified. The fragment is believed to have been fired from a .380-caliber pistol like the one Mr. Russell said he had been carrying.

The protected witness testified that a second man also fired shots in Mr. Wormsley's direction. However, Mr. Russell told police he was not aware of another gunman.

The eyewitness testified that he suffered a dislocated shoulder when he dove for cover. Mr. Thompson was pronounced dead near the entrance to the bar.