FBI Special Agent, Jay C. Newman, is well known to have been the agent wounded by "Baby Face" Nelson during the gun battle at Little Bohemia lodge in April, 1934. Newman went on to finish his FBI career and his biography is in the appropriate section at this site. Also wounded was Constable Carl C. Christensen; killed from the law enforcement ranks was SA Carter Baum.
Newman's nearly 300 page autobiography is a matter of record with the LDS Church in Utah and within that document he relates what happened that day, including his official statement to the FBI which readers will see. The below link is an excerpt from this large document covering this incident in 1934. You will see in the first paragraph or two he relates arriving in Chicago, followed by his detailed account of the shooting involving himself, SA Carter Baum, and Constable, Carl C. Christensen.
You can read the Newman account at Little Bohemia here.
Constable Carl C. Christensen was interviewed by the FBI within several days of the shooting when his statement was contemporaneous with the recent shooting.
Christensen's statement of April, 1934 is located here; these pages also contain an interview at the hospital revealing Christensen's wounds. Readers can find our brief article immortalizing Christensen in the navigation area of this site.
Finally, included here is the short statement of Henry Kuhnert which is consistent with Newman's as to where all met up.