On Tuesday, 8 February 1977 Tony Kiritsis entered the offices of Meridian Mortgage at 129 East Market Street in downtown Indianapolis and took the firm's President, Richard Hall, as a hostage, wiring a sawed-off shotgun with a "deadman's switch" to Hall's neck.
Kiritsis walked Mr. Hall through the streets of downtown Indianapolis to Kiritsis' car, eventually forcing Hall to drive to Kiritsis' apartment, where he held Hall for almost 3 days. The apartment had been booby trapped to prevent a police rescue attempt.
After intense negotiations, Kiritsis released Hall unharmed. He was arrested and charged with kidnapping, armed robbery, and armed extortion. On October 21, 1977, he was found not guilty by reason of insanity and spent a total of 11 years in custody, primarily in mental hospitals.
Kiritsis was angry with Meridian Mortgage due to a dispute about the 17 acres of land Kiritsis had purchased that he planned to develop. He believed the mortgage company was trying sabotage the project so they could assume ownership of the property.
Fred Heckman from WIBC interviewed Kiritsis during the crisis; that audio is available on YouTube. A documentary, called Dead Man's Line about the Kiritsis case was released in 2018, and is available on Prime Video. There are lots of other sources of information about the case available online, including Indy Encyclopedia which I used for some of this information.
This cache is located on the 17 acre property that was at the heart of the dispute.