A government motion seeking a reduced sentence for disgraced lobbyist Jack Abramoff also includes ominous hints that other “public officials” remain under investigation.

Abramoff is scheduled to be sentenced Sept. 4 for fleecing clients and bribing public officials.

In a memorandum prepared for that hearing, the government on Wednesday requested that Abramoff’s sentence be tempered by the “extraordinary cooperation” he has provided in nine related convictions that the government has achieved, including former Rep. Robert Ney (R-Ohio), who was released from prison last week.

The Justice Department brief also mentions that “there remain several ongoing or completed investigations of Abramoff and the relationships that he had with various public officials.”

While the brief does not offer details, the department has submitted a sealed description of these investigations to the court.

According to the brief, the ongoing investigations cover “the same type of conduct which was outlined in Abramoff’s plea documents. In other words, the allegations are that the lobbyists provided a stream of things of value to public officials in exchange for a stream of official action.”

A number of Members’ names have surfaced in connection with the Abramoff investigation because of their links to staffers or lobbyists, including Rep. John Doolittle (R-Calif.) and former Reps. Ernest Istook (R-Okla.) and Tom DeLay (R-Texas), but none have been charged with any wrongdoing.

The government is suggesting a 64-month sentence, with credit given for the two years Abramoff has already served in connection with a fraud conviction in a Florida court. This would “likely qualify as the longest sentence of any defendant in this investigation,” according to the Justice Department brief.