FOND DU LAC, Wis. (AP) — A Wisconsin prosecutor is expected to lay out the findings of an investigation into the death of a rookie state trooper last March.

Trevor Casper was on his first solo patrol when he died in a shootout with Steven Snyder in Fond du Lac. Authorities have said the 38-year-old Snyder was a serial bank robber who had just robbed a bank in Wausaukee and the 21-year-old Casper was confronting him.

READ MORE: Man Fatally Shot In South Minneapolis Identified As Christopher Crockom

They also said Snyder killed 59-year-old Thomas Christ earlier in the day not far from the site of the Wausaukee robbery.

READ MORE: Major Storm Damage In Hudson: Public Library Sustains Significant Damage, All Schools Closed Friday

Fond du Lac County District Attorney Eric Toney has a news conference Thursday afternoon.

Authorities in Snyder’s home state of Michigan said this week that Snyder was responsible for nine bank robberies in three states.

MORE NEWS: COVID In MN: MDH Reports 2,645 More Virus Cases As Latest Positivity Rate Hovers At 7.1%

(© Copyright 2015 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)