CHICAGO (CBS) — U.S. Sen. Mark Kirk said farewell to his colleagues on Capitol Hill on Friday.

A Navy Reserve veteran, Kirk described his fondest memory of his service as helping bring a Bosnian war criminal to justice. He then offered thanks to colleagues, staffers, and voters for his time in Congress.

“This institution and the U.S. military that has given rise from the appropriations we’ve given is the greatest force for human dignity that’s ever been put forward,” he said.

Kirk, who lost his bid for re-election to Democratic Congresswoman Tammy Duckworth last month then praised Illinois as a place citizens can be proud of.

“The first cell phone call in the world was made from the 50-yard line of Soldier Field in Chicago, and that trillion-dollar industry started right in the middle of our state,” he said.

The senator cited other technical achievements, and also noted the shame of former Gov. Rod Blagojevich’s conviction on corruption charges.

Then Kirk praised the World Series champion Chicago Cubs.

“Take heart, Illinois,” he said.

Kirk still has a few weeks left in office, as Duckworth won’t be sworn in as his successor until the new Senate convenes on Jan. 3.