ANCHORAGE—A 43-year-old Yellow Cab driver was arrested Sunday afternoon, accused of raping a woman, said Anchorage police, who fear the driver may have assaulted other women.   The woman told police the driver, Chidiebere Nwokorie, had offered her a ride, but ended up taking her to the cab service yard on Ship Avenue. He told her he would give her a ride home in his personal vehicle, which was parked at the yard, she told police.   Instead, she says he sexually assaulted her in the cab.   The woman ran to Ship Avenue, pants in hand, and flagged down a car. Bradley Orr, who was on his way home from the shooting range, pulled over, police said.   The woman told Orr a Yellow Cab driver had just sexually assaulted her. Orr immediately called police.   As they waited for police at 1800 Ship Avenue, Nwokorie pulled up in a Yellow Cab. The woman asked Orr to get her away from Nwokorie, but Nwokorie got out of his cab and began approaching Orr’s car, police said.   Orr retrieved a pistol from his back seat and held the driver until police arrived.   Nwokorie was arrested for first-degree sexual assault, first-degree attempted sexual assault and second-degree sexual assault.   Nwokorie’s posted his $5,000 cash/corporate bail and was released shortly after he was arrested, police said.   Police say Nwokorie will be arraigned “at a later date” since he’s “currently out of custody.”   “Because this suspect is a cab driver and has regular access to unaccompanied females, detectives are concerned that there may be other victims who have hesitated to come forward,” said Anchorage police Lt. Dave Parker in a statement.   Anyone with information about other victims is urged to call Anchorage police at 786-8900.