Prosecutors say Marcellus Jones shot and killed Tyreek Taylor to stop him from talking to police about the June 2008 killing of Drexel University graduate student Beau Zabel.
The Austin, Minn. native had moved to Philadelphia to teach a few weeks before he was shot and killed during a robbery on a South Philadelphia street.
Jones was convicted last month in Taylor's killing. The Philadelphia Inquirer reports the killing's connection to Zabel's death was detailed in a motion alleging "prior bad acts" involving the men.
Jones was sentenced to life in prison for Taylor's killing. Police say they'll continue to investigate Zabel's death.