WINNIPEG -- Manitoba RCMP is making a plea to the public for help in finding a missing Manitoba teen.

Tammy Nattaway, 16, was last seen by a family member in Garden Hill on July 20 – exactly one month ago. Mounties said it’s possible she’s gone to St. Theresa Point or Wasagamach.

Since then, there have been no other sightings of here, and RCMP said she has not been active on social media.

Police describe Tammy as five feet tall, about 100 pounds, with short black hair and brown eyes.

"Since the report was first received, our investigators have been working hard to find Tammy," said Sgt. Paul Manaigre, spokesperson for the Manitoba RCMP.

Manaigre said RCMP is treating the disappearance as a missing person investigation, adding they don't believe any foul play is involved.

"We're hoping we get information that will lead to her being found safely."

He said police have been doing house-to-house searches in Wasagamach and Garden Hill, as well as searching the surrounding brush and waterways.

"As the area is only accessible by air, a thorough review of all passengers flying out of the communities has been completed," he said, adding the Manitoba RCMP underwater recovery team also searched areas of interest.

He said underwater cameras have been purchased to help search underwater, and helicopters have been used to search the communities and surrounding forests.

"Despite all these efforts by RCMP and local community members, there have been no new sightings of Tammy, and no new information has been received on her possible whereabouts since her last appearance on July 20," Manaigre said.

"Based on all the information available, the Manitoba RCMP believe that Tammy is still within the collective area known as Island Lake," he said.

"All though unlikely – there is also the possibility that Tammy managed to travel by plane to Winnipeg."

He said RCMP needs new information to move the investigation forward and is calling on anyone with information about her disappearance to immediately call the Island Lake RCMP at 204-456-2626 or Crime Stoppers at 1-800-222-8477.

He said the Garden Hill First Nation is offering a $5,000 reward for any information that leads to finding Tammy.

"Someone must know where she is, or where she went," he said. "We need them to come forward and help."

COMMUNITY SEARCHING FOR SIGNS OF MISSING TEEN

On Friday, Garden Hill First Nation Chief Dino Flett said hundreds of volunteers helped to search the area for signs of the missing teen.

“We’re still looking,” he said.

“We’ve been going day and night trying to locate her.”

Over the weekend, more than 300 volunteers worked with the RCMP search team, looking through wooded areas and waterways in northern Manitoba.

“The dive team came and there was some interest in one area lake,” said Mark Barkman, director of operations for Garden Hill First Nation.

“They told us they found nothing.”

Barkman noted the community has been searching for Tammy every day for a number of weeks, but has come up empty-handed.

“We don’t have any leads,” he said.

- With files from CTV’s Touria Izri.