Two suspicious packages addressed to Indian-origin Senator Kamala Harris and billionaire Democrat Tom Steyer were recovered, taking the number of such packages to 14, the FBI said Friday.
Kamala, a rising star in the opposition Democratic Party and a potential presidential candidate, is the first Indian-origin US Senator. She represents the state of California.
The FBI said the suspicious package addressed to her was recovered from California.
The federal investigating agency also confirmed that a package has been intercepted in California, similar in appearance to the others, addressed to Tom Steyer.
In New York, the FBI intercepted another suspicious package addressed to former Director of National Intelligence James Clapper.
With this, a total of 14 suspicious packages have been recovered from various parts of the country.
Most of them, which the FBI identified were IEDs, have been addressed to top Democratic leaders including former president Barack Obama, former vice president Joe Biden, and former secretary of state Hillary Clinton.
Since Monday, homemade bombs and other suspected explosive devices have been addressed to Obama, Clinton, Hollywood actor Robert De Niro and a slew of figures disliked by the president's supporters.
The FBI has arrested Cesar Sayoc, 56, a resident of Florida on charges of sending package bombs. He has been charged with five federal crimes.
Sayoc, media reports said, has a criminal history and threatened Democrats on Twitter. He is reported to have frequently posted far-right conspiracy theories about the opponents of President Donald Trump.
Earlier in the day, Trump thanked law enforcement agencies for doing a fantastic job in the investigation of the case.
"I just want to compliment law enforcement for having done an incredible job. The FBI, the Secret Service -- so many. I mean, they just got together and did a fantastic job. Like finding a needle in a haystack.
"So I want to congratulate them, as you know. I think everybody wants to congratulate them. But they did a fantastic job," he told reporters at the White House.