Washington (CNN) Julian Assange faced a single criminal charge when he was pulled from the Ecuadorian embassy in London last week -- but, according to a CNN review of court records, prosecutors have already given a roadmap about how they may be continuing to investigate WikiLeaks and suggested that more charges are to come.

Legal experts have agreed that the indictment against Assange won't be the last word on his alleged crimes -- and prosecutors already have suggested it in recent weeks in several other related criminal matters. The Justice Department already expects to bring additional charges against Assange, CNN reported.

The indictment against Assange -- only six pages long -- indicates as much through its omissions.

Near the indictment's conclusion, prosecutors write about how Assange wanted to try on his own to crack passwords, among acts "in furtherance" of his and Chelsea Manning's conspiracy to break into government computers to access confidential documents. "On or about March 8, 2010," prosecutors detail, "Manning provided Assange with part of a password stored" on Defense Department computers. "Assange requested more information from Manning related to the password." Assange then said he had "no luck so far" with the attempted alleged hack.

However, Assange only faces one charge under the current indictment, related to his support for Manning's own password-cracking effort in March 2010.

The omission of more details is conspicuous, said Peter Toren, a former computer crimes federal prosecutor.

"The government does not limit an indictment, especially in a case like this, to a single count. It's a better practice for the government to bring a multi-count indictment" to the court, Toren said. "If you lost on one count, then you've lost the case. You're not going to put all your marbles in one basket."

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For now, the single count against Assange may act as a clean, succinct way for prosecutors to extradite him to the US. He is currently in jail in London, facing extradition proceedings, which could take months or even years. Assange's attorneys have so far cast the charge against him in the US as an attack on the press because his communication with Manning boiled down to encouraging her to provide information and concealing her identity as a source.

Legal scholar Orin Kerr tweeted last week that the indictment against Assange is "a placeholder." That'd mean it's "a brief indictment sufficient to get the case started, but very likely only a small part of any case against Assange," Kerr explained.

Three ongoing criminal proceedings suggest that the Justice Department continues to target Assange. Two of these are grand jury efforts to obtain testimony from witnesses -- Manning, the Army intelligence agent-turned-leaker who's central to his case, and, separately, former Roger Stone associate Andrew Miller -- who have information about Assange and Wikileaks.

The Justice Department's rules governing grand juries say they can't keep investigating after an indictment is filed, unless they are pursuing additional charges. So far, prosecutors have been coy about why they want Assange and Miller to testify, though the two have in common that they each have info about Assange and Wikileaks.

Assange's indictment was filed more than a year ago, yet a grand jury known to be investigating WikiLeaks continues to sit in the Eastern District of Virginia.

Manning was subpoenaed to testify to a grand jury in the same district in Virginia last month, a full year after Assange's sealed indictment in March 2018.

Manning contends prosecutors subpoenaed her for the wrong reasons to create a perjury trap. Yet prosecutors say that when they question her before the grand jury, it "will become clear" her testimony is "highly relevant to an ongoing criminal investigation." The prosecutors won't disclose the reason for the subpoena, though they've told Manning's attorneys she's not the target of the investigation, according to court records.

Manning is being held in jail for refusing to testify to the grand jury.

Separately, special counsel Robert Mueller subpoenaed Miller for documents and grand jury testimony in May 2018. The prosecutors sought documents related to Stone and Russian hackers who stole Democratic party emails in 2016 -- two targets well-trod by Mueller. Yet they also looked for documents related to Assange and WikiLeaks, Miller's attorney said in a recent court filing. The grand jury used by Mueller to subpoena witnesses still appears to be sitting, having met as recently as April 5, though the prosecutors or the court haven't confirmed this since Mueller concluded his investigation last month.

Stone was charged with witness tampering, obstruction and lying to Congress in January, but prosecutors wrote to a federal judge in Washington on Friday that Justice Department offices outside of Mueller are still investigating in a way that "sweeps more broadly than Stone and the specific crimes with which he has been charged."

Miller continues to appeal his subpoena, though he's lost his challenge in court twice already.

On Monday, a federal judge in New York City also noted how a criminal investigation related to yet another alleged WikiLeaks leaker is ongoing.

The case, against former CIA software engineer Joshua Schulte, had originally begun as a child pornography case in August 2017 -- the type that's routinely prosecuted by federal authorities.

But in June 2018, prosecutors added to the charges against Schulte, alleging he illegally gathered classified information from the CIA on his computers with the intent to harm the US. He allegedly sent the info to WikiLeaks -- called "Organization-1" in the court record, which posted the documents. It's known as the "Vault 7" leak.

Schulte has pleaded not guilty to the charges he faces, and his trial is set for November.

Schulte in recent weeks has tried to tell the federal court "time is up" and the "investigation is over," a federal judge noted on Monday. But prosecutors assured the court this month the investigation is continuing.

For that reason, they want to keep search warrants in the case confidential.

"Even today, dissemination of the search warrant materials to third parties 'could, among other things, jeopardize the safety of others and national security, and impede ongoing investigations,'" prosecutors wrote on April 2, quoting a still-in-place court order that locks down documents in the case.

On Monday, the federal judge in Manhattan, Paul Crotty, agreed with Schulte's prosecutors, taking their assertion of an ongoing investigation at their word.