Federal agents descended Tuesday on the home and offices of state Sen. Martin Sandoval as part of an ongoing criminal investigation, adding him to the growing list of city and state politicians facing serious scrutiny.

Feds in suits could be seen lugging boxes, electronics and a bag marked “Evidence” from the state capitol building in Springfield. A similar scene played out at Sandoval’s Southwest Side home. And agents could be seen outside Sandoval’s political office in Cicero.

FBI Special Agent John Althen confirmed the agency had personnel in the state capitol conducting “authorized law enforcement activity,” but he declined to comment further. IRS Criminal Investigation was also involved in the search, according to an official there.

The first-floor Capitol suite targeted by the feds in Springfield contains the offices of several senators, but it was apparent Tuesday the agents were focusing on the office of Sandoval, who is the Democratic Caucus whip. Through translucent windows, reporters outside could see people moving inside that office, with occasional camera flashes visible.

Several calls and messages seeking comment from Sandoval went unanswered. Federal agents could be seen at his home in Gage Park, though. Nearby sat a black SUV with an FBI Chicago field office placard in the window.

Two men emerged from the home about 2:25 p.m. dragging multiple rolling containers. The men, who were in plainclothes, didn’t identify themselves when reporters asked, but at least one of them was armed with a handgun and had handcuffs on his waistband.

Four agents left the home around 2:50 p.m. carrying multiple boxes and one computer. One agent told reporters that Sandoval wasn’t home during the raid. A person answering the door told a reporter to call Sandoval’s office.

Though the purpose of Tuesday’s coordinated raid was unclear, it’s the latest public signal of multiple, ongoing investigations into public officials in Chicago and Illinois. The first arrived when the FBI last November raided the City Hall office of Ald. Edward M. Burke (14th), who has since been hit with a 59-page racketeering indictment. Former Ald. Danny Solis (25th) has also been outed as a cooperator who recorded Burke.

The feds conducted a similar raid in June on the offices of Ald. Carrie Austin (34th), though she has not been charged with any wrongdoing.

Meanwhile, state Sen. Thomas Cullerton found himself under indictment in August. Associates of Illinois House Speaker Mike Madigan, including former Ald. Mike Zalewski (23rd), have also been circled by the feds in recent months. And ComEd has acknowledged a subpoena targeting its lobbying activities.

Asked about the Sandoval raid Tuesday, Mayor Lori Lightfoot called it “interesting.”

“We have been hearing for a long time that the federal investigation is of longstanding and has a lot of different tentacles,” Lightfoot said. “Certainly, I paid attention that the outgoing [special agent in charge] of the FBI essentially said, ‘More to come.’ So, it looks like there’s more to come.”

Lightfoot said she is “not surprised” by the raid. But she has “no specific knowledge about Sandoval one way or another.”

Sandoval represents an area on the southwestern side of Cook County — one represented in part both by Madigan and Burke. He was elected in 2002 with the help of Mayor Richard M. Daley and now chairs the Senate’s transportation committee. Sandoval gained national attention about a month ago after social media posts showed a man at his political fundraiser pretending to shoot someone wearing a Donald Trump mask.

Sandoval said he had no knowledge the mock assassination was happening. The photo was widely condemned by politicians on both sides of the aisle. After issuing an apology, Sandoval later placed the blame on a vendor and guest with bad judgment.

Contributing: Fran Spielman and Capitol News Illinois