Investigators are pleased with their progress looking into a suspicious fire that destroyed a northeastern Forsyth County home Jan. 18.

Noting that some arson investigations take years, Forsyth County Fire Marshall Steve Anderson said he is satisfied with how the probe into the Lanier Drive blaze is coming along.

"We do have leads we are following up on that are promising," he said. "I can't say how long it will take."

Anderson said the Bureau of Alcohol, Tobacco, Firearms and Explosives is still involved in the probe, which is now in its third week.

In addition to the fire, someone spray-painted graffiti that included a racial slur and the phrase "your black boy will die" on a fence along the property.

The Forsyth County Sheriff's Office is looking into the writing, but has not released details of its findings.

Anderson said the FBI continues to monitor the case as it unfolds.

"We have done a neighborhood canvas, which is a normal procedure," he said, adding that authorities have received "useful information" from the community and tips from the county's Crime Stoppers hotline.

No suspects or persons of interest have been named and Anderson would not say whether anyone has been eliminated from suspicion.

He also declined to release details about the cause and origin of the fire.

"This is a set fire, which of course is a crime, and we want to keep some things to ourselves that only we and the person who perpetrated it would know," he said.

The homeowner, Pam Graf, has said she left with a friend Jan. 16 for the presidential inauguration in Washington, D.C., returning late Jan. 19 after learning about the blaze.

Graf, who is a supporter of President Barack Obama, contends the fire and graffiti were politically motivated.

A couple weeks earlier, a threatening note turned up in her mailbox, she said. The message included a racial slur and the phrase "watch your back."

Graf said she did not notify authorities because she didn't take it seriously. But she did remove an Obama campaign sign from her yard. Another sign had disappeared prior to the Nov. 4 election.

Anderson has received several phone calls from residents who want to help Graf, but said he does not know of any organized efforts that have been formed.

"At the time of the fire, if we have people that need immediate assistance, we go through the Red Cross to provide it," he said. "After that, we do not get involved in support ... it would be improper for us to get with her and discuss this."

As far as authorities can determine, Anderson said, Graf was the only person living in the five-bedroom house.

Without going into specifics, Graf said Friday she is grateful for the community's support and hopes it will continue. She also said she is concerned about her safety.

"That's my main worry is for my children and for me," she said.

Graf has three children ages 11, 14 and 17. According to Forsyth County Superior Court records, they live with their father.

The fire occurred about 4:30 a.m. Jan. 18 and burned the nearly 3,000-square-foot home to the ground. County tax records list the total value of the house at $255,490.

State Farm insurance investigators are also searching for answers.

"The insurance company is obligated by their contract with her," Anderson said. "We are still communicating with the insurance company and when possible they are providing us information that we might need."