Updated

The family of a Texas man who was shot and killed last year is using an interstate highway billboard to garner new information that could lead to arrests.

John Martinez was gunned down by three men outside his home in Houston on Oct. 13, 2012, KHOU reports.

“I really strongly believe that they were trying to come in the house. My husband stopped them, and I tell my children, 'he’s our hero',” his widow, Norma Martinez, told the station. “He didn’t deserve this, we didn’t deserve this, and my children shouldn’t be without a father right now.”

After Martinez’s murder, 50-year-old Criss Knight was killed 28 days later with the same gun, leaving detectives to believe the cases may be linked. Witnesses say Knight’s killers fled the scene of that shooting in a black pickup truck, which is one of the few leads in the case, KHOU reports.

The Martinez family billboard, which is along I-45, offers a $5,000 reward for information related to the case.

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