A former NFL player is missing and his mother is dead as police in Illinois launched an investigation over the weekend into the mysterious circumstances.

Family members of Sergio Brown and his mother, Myrtle, contacted authorities on Saturday to say they couldn’t find or make contact with either person, Maywood police said. A missing persons search was started and 73-year-old Myrtle Brown was found dead in a creek near her home, according to FOX 59.

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Authorities were investigating Myrtle Brown’s death as a homicide.

Sheila Simmons, the sister of Myrtle Brown, told WGN-TV that she last talked to her on Sept. 14 and that the woman just celebrated her birthday on Sept. 8. Simmons said she received a phone call around 3 a.m. local time that her sister and nephew were missing.

"We’re going to find out what happened because it’s not normal for my sister to not answer her phone, not to respond to text messages. People have been reaching out to her since Friday. No one was able to reach her," Simmons told the station. "Now, I got the call this morning saying that she’s missing, so immediately I came out here and find out my sister is dead."

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Simmons added that she went back to the home in Maywood and noticed things were out of place, according to FOX 59.

Family members told WGN-TV they hadn’t heard from Sergio Brown.

Sergio Brown, a former Notre Dame football standout and Maywood native, signed with the New England Patriots in 2010 as an undrafted free agent.

He played seven seasons in the NFL with the Patriots, Indianapolis Colts, Jacksonville Jaguars and Buffalo Bills. He last played in the league in 2016.