The Federal Bureau of Investigation (FBI) has called on hundreds of agents from specialized squads and field offices across the country, as its Capitol riot investigation moves to a new level, with attempts to build conspiracy charges against the growing number of suspects.

Wall Street Journal reported that officials are looking through evidence, which includes more than 200,000 digital tips from social media, public members, confidential informants, local news, and surveillance footage.

According to court filings, the probe now includes FBI agents who normally handle other matters such as securities fraud, public corruption, drugs, and gangs.

From Arizona to New York, FBI field offices and officials have made arrests, search homes, and interview witnesses, as well as family members and associates.

According to filings and people involved, Homeland security agents and local law enforcement have also been joined the investigation. 

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FBI's Scope of Investigation

Current and former law enforcement officials said the effort was comparable with some of the largest investigations in the FBI's recent history, like the Oklahoma City bombing and the Boston Marathon attack.

Officials said that the efforts are made to deter future plans to besiege the capital and root out dangerous groups.

"The scope and scale of this investigation and these cases are really unprecedented not only in FBI history, but probably DOJ history," Michael Sherwin, acting U.S. attorney for the District of Columbia, said in a report.

Sherwin said at a recent news conference that there were thousands of potential witnesses and likely hundreds of criminal cases.

Richard M. Frankel, the former special agent in charge of the Newark, N.J., FBI field office, said the breach of the Capitol gave the FBI a starting point to investigate white nationalist groups long on law enforcement's radar. Frankel added that this allows for a review of finances, communications, and affiliations.

At least 71 cases involve photos, posts, or footage from social media. Also, at least 47 people saw screenshots of their own posts, live streams, or videos in their charges, USA Today reported.

Meanwhile, Parler said it welcomes calls from the House Oversight Committee for a robust examination of its policies, adding that it has been cooperating and will continue to do so, according to a Fox News report.

"Like other social-media platforms, we have been cooperating and will continue to cooperate with law-enforcement efforts to identify and prosecute those individuals responsible for organizing and carrying out the shameless Jan. 6 attack on the Capitol," Parler Chief Operating Officer Jeffrey Wernick said in the report.

He added that the social media platform welcomes Rep. Carolyn Maloney's call to have the FBI conduct an extensive examination of Parler's policies and actions.

Wernick's statement came after Maloney sent a letter to the FBI on Thursday, urging the agency to review whether Parler played a role in facilitating a plan or inciting a riot at the Capitol.

In the letter, Maloney said it is clear that Parler holds additional evidence needed on the investigations at the Capitol's attack.

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