A week before a Maryland mother of 5 disappeared, another Marylander vanished while on her evening walk in a local park.

Mariame Toure Sylla, 59, is a 2nd grade teacher at Dora Kennedy French Immersion School in Greenbelt,  a Washington, D.C., suburb some 55 miles from Bel Air — on the opposite side of Baltimore from Greenbelt — where 37-year-old Rachel Morin was found dead just off a popular hiking trail on Sunday. Police launched a homicide investigation, although they have not yet said how she died, as CrimeOnline previously reported.

Sylla, however, has not been found.

The beloved teacher was last seen on July 29 heading out for a walk in a nearby park at about 8 p.m., NewsNation reported. It was a walk she took almost every day in Schrom Hills Park, usually lasting for 30 to 45 minutes. But this time, she didn’t return.

Investigators, aided by members of the community, have been searching the area and following up on “all leads that have come to us,” Greenbelt Police Chief Richard Bowers said.

“We keep all of our possibilities open as to the cause of her disappearance.” he said.

Last week, students and parents were door-to-door asking for clues. Police said all of Sylla’s belongings and medications were found in her home, and friends say that she is a devout Muslim who never misses daily prayers.

It’s not clear who reported Sylla missing. Morin was reported missing by her boyfriend, who also told police where to find her car and then posted on social media that he loved her and was not responsible for her death. Police have not named a suspect.

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[Featured image: Mariame Toure Sylla/Greenbelt Police Department and Rachel Morin/Harford County Sheriff’s Office]