OAKLAND, Calif. - A BART officer said Tuesday that an unarmed black man who was fatally shot by another officer at an Oakland train station failed to obey her commands before his death.

Bay Area Rapid Transit Officer Marysol Domenici testified during the fourth day of a hearing to determine whether former BART officer Johannes Mehserle will stand trial for murder for killing Oscar Grant.

The 22-year-old Hayward man was shot in the back as he lay face down on the train station platform early New Year's Day as officers tried to quell a group of unruly passengers.

Domenici said Grant and his friends yelled profanities and did not obey her orders to sit down moments before Mehserle fired at Grant. She said she was fearful when heard taunts coming from Grant, his friends and passengers on the train.

"People were saying 'I'm going to get your name and badge number... (Expletive) BART Police, you don't know anything, you're just security guards,'" Domenici said during testimony in Alameda County Superior Court.

"We're outnumbered and nobody's complying with our orders," she said. "They were just all over the place. At that point, yeah, you feel for your life and safety."

Domenici said at one point Grant also grabbed her left arm as she tried pushing another one of his friends to the ground. Her partner, Tony Pirone, then came over and hit Grant, pushing him to the ground, she said.

Mehserle's lawyer Michael Rains said his client, who has pleaded not guilty, intended to use his stun gun but accidentally fired his pistol instead.

Rains said Tuesday that Pirone will testify that he heard Mehlserle say he was going to use a stun gun moments before shooting Grant. Pirone is scheduled to testify as early as Wednesday.

Rains also said he plans to show enhanced video that shows Grant tried to resist arrest.

Both Pirone and Domenici remain on paid leave. Their names are both mentioned in a $50 million wrongful death lawsuit filed by Grant's family in March against BART.

During other testimony Tuesday, BART officers Jon Woffinden and Emery Knudtson both described a tense scene between transit police and passengers shortly before the shooting.

Deputy District Attorney David Stein, however, tried to point out inconsistencies in their testimony using video footage of the shooting compared to their written police reports.

Grant's uncle, Cephus "Bobby" Johnson, said after Tuesday's hearing that the officers were participating in a "cover-up" for each other.

Domenici is scheduled to be back on the stand on Wednesday.