The prosecution of the two suspects in the cell phone bandit bank robberies will be consolidated in federal court in Alexandria, after Loudoun County prosecutors agreed yesterday to dismiss their case against the woman accused of robbing four banks.

Police and federal agents arrested Candice R. Martinez, 19, last week on warrants from Fairfax and Loudoun counties. She was identified after a surveillance video of a Nov. 4 holdup at a Wachovia bank branch in Ashburn was broadcast nationally. In that holdup, the robber never put down her cell phone while obtaining about $20,000 from a teller, according to court records.

Loudoun Commonwealth's Attorney James E. Plowman initially resisted handing Martinez over to federal authorities, saying he had not been given a reason to dismiss his robbery case. But yesterday, Plowman said he had decided it would be best if all four holdups were prosecuted in one place.

"It's in the interest of judicial efficiency," Plowman said. "If they do them all in one courthouse, you're going to save on witness time and evidentiary issues, because it's all secured in one location."

Martinez's boyfriend, Dave C. Williams, 19, of Fairfax, was arrested first, on Nov. 14. Court records show that he provided a handwritten statement saying that he and Martinez planned all four robberies and that he was on the cell phone outside each bank talking to Martinez while she went in and demanded cash from tellers.

Williams was charged in federal court in the first of the four holdups and taken into federal custody. An FBI agent testified at Williams's preliminary hearing that $48,000 was stolen in the four robberies.

Ten hours after Williams was arrested, Martinez, a community college student from Santa Fe, N.M., was arrested in Centreville. She was questioned at Fairfax police headquarters and also told authorities of her involvement, court papers say. Federal authorities also charged her in the first of the four robberies.

Fairfax prosecutors, at the request of federal prosecutors, dismissed their case against Martinez last Wednesday. Loudoun then picked her up Thursday afternoon, and she was arraigned there Friday.

Plowman said Loudoun authorities had to bring Martinez to Leesburg to either prosecute or dismiss her warrant there. "She's got to come to Loudoun and appear before a judge," Plowman said. "We weren't whisking her away from Fairfax."

Court papers say Martinez and Williams have implicated themselves in four holdups -- Oct. 12 in Vienna, Oct. 21 in Manassas, Oct. 22 in Springfield and Nov. 4 in Ashburn -- all at Wachovia branches. Federal prosecutors could seek to indict them as soon as next month for all of those robberies.