CHICAGO — State Sen. Donne Trotter on Wednesday was busted for bringing a handgun and bullets through an O’Hare Airport security checkpoint on his way to catch a flight to Washington, D.C., sources told DNAinfo.com.

Trotter, who last week announced he would seek the Congressional seat vacated by former U.S. Rep. Jesse Jackson Jr., was charged with felony attempt to board an aircraft with a weapon, law enforcement sources said.

TSA agents discovered an unloaded .25 caliber pistol and a clip loaded with live rounds packed inside Trotter’s garment bag about 8 a.m. Trotter told investigators that he worked the late shift for security for Allpoints Security and Detective Inc. the night before and didn’t realize the weapon and bullets were in his bag when he packed for his trip, sources said.

Trotter remains in custody pending a bond hearing and couldn’t be reached for comment. A spokesman at Trotter's Chicago office declined comment.

Trotter had a valid firearm owner's identification card that was registered to his Senate office at the state Capitol building, sources said.

But it was unclear whether the pistol was registered in Chicago as required by the city’s handgun ordinance.

Trotter, who lives in South Shore, served in the state House from 1988 until 1993 when he won the state Senate seat he still holds.

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