FBI agents have been tracking down members of Mark Foley’s former congressional staff as part of a criminal investigation into the congressman’s sexually explicit Internet messages with teenage boys who were former congressional pages. Staffers have been questioned this week in what were described as "short, pointed interviews." One former Foley staffer said the agents are attempting to determine if Foley’s contact with underage pages went beyond exchanges of sexually explicit e-mails and instant messages to actual physical encounters. THE BLOTTER RECOMMENDS Foley Cruising in His BMW; Another Dorm Visit in 2000 DISCRETION ADVISED: The Instant Messages That Forced Congressman Mark Foley’s Resignation Click Here for More of the Brian Ross Page Several former staffers have told ABC News they were unaware of Foley’s activities. Foley’s Capitol Hill office computers have been secured, and the Department of Justice has advised members of Congress and Foley’s staff to "maintain" any documents or computer records that could be connected to the investigation.