A man who owed money to 75-year-old black activist Sadie Roberts-Joseph has been arrested for her murder in Baton Rouge, Louisiana, police announced Tuesday .

Roberts-Josephs body was discovered in the trunk of her car on Friday after an anonymous tip was received by the Baton Rouge Police Department. On Monday, the department ruled her death a homicide .

Ronn Germaine Bell, a tenant of Roberts-Joseph, was charged with first-degree murder in the case. While police said the killings motive was still under investigation, they said Bell lived in one of Roberts-Josephs rental houses and was $1,200 behind on rent.

Bell, 38, pleaded guilty in 2007 to the sexual battery of a young girl and served seven years in prison, according to The Advocate, Baton Rouges newspaper.

Bell is black, and authorities said the crime did not appear to be racially motivated.

There is no information which leads us to believe that this is a hate crime, Police Chief Murphy Paul said. There is no information which leads us to believe that this incident was motivated by Ms. Sadies activism or her community efforts.

Roberts-Joseph was the founder of the Odell S. Williams Now and Then African American Museum in Baton Rouge and a prominent community leader and civil rights activist. Her death was mourned across the city.

Im heartbroken that our community has lost such a kind and selfless soul in such a violent and tragic manner. Ive known and loved Ms. Sadie for years, and admire and respect her dedication to education and our community, East Baton Rouge Sheriff Sid Gautreaux said.