There is a mystery unfolding tonight in a Bethesda neighborhood.

Ten days ago, a fire killed a man inside a home on Danbury Road. Investigators have been on the scene ever since.

Neighbors' reactions range from curious to inconvenienced to concerned.

Many didn't want to talk on camera, but wondered if the presence of workers in hazmat suits meant the area is unsafe.

RELATED: 1 dead, 1 hospitalized after fatal house fire in Md.

Andrew Bonior walked his dog, Buster, nearby, and he sums it up, "Something else happened in there, there's more to this story."

It happened on Sunday, September 10th. WUSA9's Debra Alfarone covered this fire and learned a man died there. She also found out WUSA9 reporter Bruce Leshan lives behind the house. He tried to get people out. He called 911.

"One of the neighbors said 'I think there might be somebody in there,' so I'm like 'oh my God' and I went to the front door, and I pushed on the front door really hard. I pushed the front door away and there was something blocking it. I understand that there's a lot of stuff inside that house," said Leshan.

He said 26-year-old Daniel Beckwitt lives in the home. He is OK, but another man died. Investigators still haven't identified him nor his cause of death.

Investigators have blocked the home with fence, crime tape and firetrucks. They even set up porta-potties. On Wednesday, we saw investigators in hazmat suits there. Neighbors want to know why their road is blocked.

"There's been stories, they mention a hoarding situation, could be anything from someone survivalist in an underground bunker, because there were tunnels supposedly coming out all the way to the street. I hate to think it was more devious," said Bonior.

Firefighters did say there was a lot of stuff inside. Police didn't use the word bunker, they called it an "excavation." What it was used for is still a mystery. A bobcat sits in the backyard, sunk in a hole.

All police will say is this is an active death investigation and investigators will be here until they determine who they man is and how the died. Police say the Medical Examiner is still reviewing toxicology results for the deceased man.