The FBI on Tuesday released new video footage of a person suspected of placing pipe bombs near the headquarters of the Republican and Democratic national committees the night before the Jan. 6 riot at the U.S. Capitol, asking for the public’s help in identifying the elusive figure.

The new footage depicts the suspect, wearing a gray hooded sweatshirt and a mask, in four separate clips. The FBI said it was offering a reward of up to $100,000 for information leading to the suspect’s location, arrest and conviction.

“These pipe bombs were viable devices that could have been detonated, resulting in serious injury or death,” Steven M. D’Antuono, assistant director in charge of the FBI’s Washington field office, said in a statement. “We need the public’s help to identify the individual responsible for placing these pipe bombs to ensure they will not harm themselves or anyone else.”

The FBI had in late January released pictures and information about the person placing the pipe bombs, including of fairly distinctive black and light gray Nike Air Max Speed Turf shoes with a yellow logo that investigators believe the person wore. Their releasing more video suggests agents might be particularly vexed to identify the person responsible.

The FBI on March 9 asked the public for help identifying the suspect responsible for placing pipe bombs in Washington, D.C., on Jan. 5. (FBI)

While the person’s face is not visible in any of the new clips, the bureau asked those who watch it to take note of the suspect’s “gait, body language, or mannerisms.” They said the person is believed to have placed the pipe bombs between 7:30 p.m. and 8:30 p.m. Jan. 5. They were not discovered until the next day, when a mob supportive of then-President Donald Trump stormed the Capitol. The bureau said the devices were composed of “1x8-inch threaded galvanized pipes, a kitchen timer, and homemade black powder.”

A little after 7:40 p.m., according to the new footage, the person can be seen meandering on South Capitol Street, holding a backpack, as someone walking a dog passes by. At 7:52 p.m., the person can be seen at the corner of Canal Street SE and South Capitol Street SE, near the DNC, sitting on a park bench and appearing to reach into a backpack before getting up to walk away. At 8:14 p.m., the person can be seen walking in an alley between the RNC and the Capitol Hill Club holding a backpack. Then the person can be seen walking in front of the club and appearing to stretch.

“We are asking the public to come forward with any information that could assist us, including any odd or out-of-character behavior you noticed in a family member, friend, or co-worker, leading up to or after January 5th,” the bureau said in a statement. “On the evening of January 5th, we are asking for information about an individual who you may have observed matching this description in the vicinity of North Carolina Avenue SE, and Folger Park between 6:30 p.m. and 9 p.m.”

The bureau also said the person “may have entered a vehicle or taken an item from a vehicle and placed it into the backpack.”

Anyone with information is asked to call the FBI at 1-800-CALL-FBI, or to submit a tip online at tips.fbi.gov.