The U.S. Federal Bureau of Investigation has released new surveillance videos it says show a person suspected of planting two pipe bombs the night before the siege at the U.S. Capitol.

The pipe bombs, which were later defused, were placed outside the headquarters of the Democratic and Republican national committees - both a few blocks from the Capitol.

Authorities have charged more than 300 people in connection with the Jan. 6 events but the FBI has yet to identify the suspect who planted the explosive device.

"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 Jan. 5," CBS News quoted the FBI as saying in a news release.

Videos released last month showed the suspect walking in the neighborhood, wearing a gray hoodie and a mask and carrying a backpack, which the FBI said was used to carry the bombs.

Based on a report obtained by CBS News, the explosives contained one type of detonation - a 60-minute kitchen timer. The report suggested there was no proof of a second or remote detonation method like a cellphone.

According to Steven D'Antuono, the FBI's Washington, D.C. director, the bureau believes someone is still "out there who has information they may not have realized was significant until now." He said the public's assistance could prevent harm to others.

The FBI and the Bureau of Alcohol Tobacco Firearms and Explosives are offering a  $100,000 reward for information.