The danger to the public and to law enforcement officers from explosive devices during expected upcoming protests "is substantial," the Federal Bureau of Investigation warned in a new awareness bulletin obtained by ABC News on Friday.

The document is full of photos of devices used in the last eight months against civilian and law enforcement targets during public demonstrations.

"Devices targeting infrastructure also increased following violent activity during this time period," the bulletin states.

The FBI now wants to make first responders aware of what has been deployed in the past and what they might encounter during protests linked to the presidential inauguration on Jan. 20.

"The danger posed to law enforcement officers and the general public from the all the tactics listed is substantial," the bulletin states. "If a suspicious item is reasonably believed to contain explosives, an IED, or other hazardous material, DO NOT touch, tamper with, or move the item. Only bomb disposal personal should handle any suspected devices that are located."

An internal FBI bulletin obtained by ABC News earlier this week stated that armed protests are being planned at all 50 state capitols as well as at the U.S. Capitol in Washington, least through Inauguration Day.

The warning comes after suspected pipe bombs were found last week outside both the Democratic National Committee and the Republican National Committee headquarters, just a few blocks from the Capitol where pro-Trump rioters stormed the building.

-ABC News' Aaron Katersky

Biden has chosen Dr. David Kessler, former commissioner of the Food and Drug Administration (FDA), to help lead the federal government's COVID-19 vaccine initiative.

Kessler, a pediatrician and lawyer who headed the FDA from 1999 to 1997 under the Bush and Clinton administrations, will replace Dr. Moncef Slaoui, who is the current chief science officer to Operation Warp Speed.

Biden also announced several other appointees who will join his incoming administration's COVID-19 response team.

"We are in a race against time, and we need a comprehensive strategy to quickly contain this virus," the president-elect said in a statement Thursday. "The individuals announced today will bolster the White House’s COVID-19 Response team and play important roles in carrying out our rescue plan and vaccination program. At a time when American families are facing numerous challenges I know these public servants will do all that is needed to build our nation back better."

With just five days until his inauguration, Biden announced Thursday his pick to head the Federal Emergency Management Agency (FEMA) along with several other key posts for his incoming administration.

Deanne Criswell is his nominee for FEMA administrator. Janet McCabe is his nominee for deputy administrator of the Environmental Protection Agency (EPA). Shalanda Young is his nominee for deputy director of the Office of Management and Budget. Jason Miller is his nominee for deputy director for management at the Office of Management and Budget. And David Cohen is his appointee for deputy director of the Central Intelligence Agency (CIA).

"These dedicated and distinguished leaders will bring the highest level of experience, integrity, and knowledge to bear on behalf of the American people," Biden said in a statement Thursday. "Each of them brings a deep respect for the civil servants who keep our republic running, as well as a keen understanding of how the government can and should work for all Americans. I am confident that they will hit the ground running on day one with determination and bold thinking to make a meaningful difference in people's lives."

Alex Padilla, California’s Secretary of State and the man who will fill Vice President-elect Kamala Harris’ seat in the Senate, told ABC News he’s prepared to balance both the impeachment trial and response to COVID-19 when he’s sworn in next week.

“We have to be able to walk and chew gum at the same time,” Padilla said. “It’s not either or, COVID-19 response is absolutely important. Holding President Trump accountable is extremely important. And doing our part, as the Biden-Harris administration settles, is also extremely important. So we're prepared to do what it takes.”

He said he doesn’t know how the Senate will vote, but believes a “rebalanced leadership” with Democrats in the White House, Senate and House, will give the party “tremendous opportunity” to achieve their goals.

When asked whether he believes last week’s riot at the Capitol would embolden further attacks, he said, “Frankly, when I saw the images last Wednesday, it only emboldened my resolve to want to get to work, and want to get to work quickly.”

-ABC News' Allie Yang

House Leader Steny Hoyer, D-Md., began by stressing that Trump's action's last week "demand urgent, clear action by the Congress," and praised House Republican Conference Chair Liz Cheney and a handful of Republicans for agreeing with Democrats that Trump ought to be impeached.

"This is the daughter of the former Republican whip and former vice president of the United States of America. She knows of what she speaks, and she said this as well, 'There has never been a greater betrayal by a president of the United States of his office and his oath of Constitution," he said. "This is not, as Liz Cheney said, just some action. She characterized it as the biggest betrayal of any president of the United States in our history."

Hoyer went on to list GOP Rep. John Katko of New York, the ranking Republican on the Homeland Security Committee who Hoyer described as "not some back-bencher on your side of the aisle" and Rep. Adam Kinzinger of Illinois, among the five House Republicans who have publicly stated they'll vote to impeach the president.

"Mr. Kinzinger said this," Hoyer said, "If these actions are not worthy of impeachment, then what is an impeachable offense? There is no doubt in my mind that the president of the United States broke his oath and incited this insurrection."

Hoyer said other Republicans who he has talked to "in the past 24 hours" agree the president's actions are impeachable.