Democratic leaders of five House committees are seeking an immediate briefing from the FBI on its investigation of Wednesday’s violent breach of the Capitol, which left four people dead and disrupted a congressional proceeding to confirm the results of the presidential election.

In a letter Thursday to FBI Director Christopher Wray, the lawmakers called the riot “a deadly terrorist attack” incited by President Donald Trump and his supporters.

The lawmakers wrote, “Given the incendiary environment caused and exacerbated by President Trump’s rhetoric, along with the upcoming inauguration of President-elect Joe Biden, it is imperative that the FBI leverage all available assets and resources to ensure that the perpetrators of this domestic terrorist attack and those who incited and conspired with them are brought to justice and that this domestic terrorist group is disrupted from further actions against our government.”

The letter was signed by Oversight Committee Chair Carolyn Maloney, Judiciary Chair Jerry Nadler, Homeland Security Chair Bennie Thompson, Intelligence Chair Adam Schiff, and Armed Services Chair Adam Smith.

According to The Washington Post, acting U.S. attorney Michael R. Sherwin said federal agents and prosecutors would look into the incendiary statements made by speakers at Trump’s rally.

The Associated Press reported that Sherwin plans to file 15 federal cases on Thursday, including crimes of unauthorized access and theft of property.

Forty other cases have already been filed in District of Columbia Superior Court, Sherwin told The AP.

The FBI asks for the public's help with tips, photos, and videos to help identify those who participated in the riot.