Eric Swalwell Confronted by FBI at San Francisco Airport, Electronics Seized

The FBI reportedly gave Eric Swalwell quite the welcome home to California ... meeting him at the airport and seizing his electronics.

Agents were reportedly waiting when the former congressman landed at San Francisco International Airport Saturday ... confronting him with a search warrant and taking his cell phone and other devices.

Swalwell reportedly cooperated, but the feds weren't finished ... agents reportedly showed up at his Washington, D.C. home Sunday with additional court-approved search warrants ... seizing more potential evidence while neither Swalwell nor his wife, Brittany Watts, were home.

The searches allegedly are part of a federal criminal investigation into sexual misconduct allegations against Swalwell.

As TMZ previously reported, at least four women have accused Swalwell of misconduct ... including a former staffer who alleged he raped her when she was too intoxicated to consent.

Another woman, Lonna Drewes, publicly accused Swalwell of drugging, choking and raping her.

Swalwell has vehemently denied the sexual assault and misconduct allegations ... though he has acknowledged making "mistakes in judgment" and apologized to his wife.

The scandal torpedoed Swalwell's political career -- he dropped his campaign for California governor and resigned from Congress.

And, as we reported in May, Swalwell and Brittany were living separately amid the fallout.