Authorities hope to collect DNA evidence after exhuming the body of a southeast Missouri nursing student who was killed in 1992.

The body of Angela Mischelle Lawless was exhumed Tuesday, 21 years after she was found dead in her car on an Interstate 55 exit ramp in Benton. The 19-year-old was shot three times and struck in the head.

An Illinois teenager, Josh Kezer, spent 16 years in prison for the killing before being exonerated in 2009.

Scott County Sheriff Rick Walter reopened the case in 2006, because he believed Kezer was innocent.

The Southeast Missourian reports that Walter says authorities are trying to collect DNA from wounds that weren't tested after Lawless was killed.

Samples were taken from Lawless' body and she was reburied Tuesday evening.

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