Annapolis Mansion Fire - A fire destroyed a waterfront mansion in Anne Arundel County Monday and police are still continuing to look for six family members that went missing following the Annapolis mansion fire. Six family members are now "unaccounted for." However, fire officials said they were last seen inside the home.

Officials have declined to identify the missing family from the Annapolis mansion fire. Still, colleagues and neighbors told ABC7 News that technology executive Don Pyle, his wife Sandra, and the couple's four grandchildren, were inside the home. Property records reportedly indicate that Pyle, his wife, Sandra, and their two adult sons resided in the home which sits on eight acres and was assessed at more than $6.6 million, according to The Washington Post.

A headteacher at a local school called Severn School sent out a letter to staff and students Tuesday confirming the death of the family from the Annapolis mansion fire.

The school's headmaster, Douglas Lagarde, announced Tuesday that it would be closed out of respect for the tragedy, The Capital reported. They are assuming that Pyle's grandchildren were enrolled at the Lower School of the $17,770 a year private prep institution.

The family members who died at the Annapolis mansion fire were last seen inside the home on Childs Point Road in Annapolis, according to Lt. Craig Oldershaw of the Anne Arundel Fire Department.

Early Monday morning, the 16,000-square-foot mansion's four-alarm fire broke out. The Annapolis mansion fire reportedly resulted in the roof and the first and second floors of the house to collapse into the basement, according to authorities. Crews still have not been able to search the entire house since much of Monday was spent dealing with "flare-ups" from the blaze, according to fire officials.

On Tuesday morning, a news conference Tuesday was held near the home. Authorities called the Annapolis mansion fire a "serious fire." They also said that they are expecting to be at the mansion for several days just removing debris. As of Tuesday morning, no rescue workers had been inside the mansion yet.

Fire department crew, in addition to a national response team from the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) are reportedly expected to continue their search Tuesday and investigation of the cause of the Annapolis mansion fire. According to fire officials, they do not believe there is anything suspicious about the case.

"This is five standard sized houses put together," said Capt. Robert Howarth, a commander with the Anne Arundel County Fire marshal's office, saying how much of a challenge the large size of the home was for firefighters.

He added that he expects crews will be able to go inside the home Wednesday as soon as the necessary equipment arrives at the scene of the Annapolis mansion fire.

Heavy equipment was brought in Tuesday to secure the house and assist with moving large portions of the remaining structure, especially since several beams weighed a ton or more, reports WJLA.

Meanwhile, the cause of the Annapolis mansion fire is still under investigation.

"We have no witness who can tell us where this fire started," Howarth said. "We can't determine the origin without an investigation."

Authorities are reportedly entering the investigation of the Annapolis mansion fire with "no expectations." Howarth added that they are gathering evidence as if it is a "criminal investigation" in case of the possibility of foul play.

Spokesman and ATF Special Agent David Cheplak said Tuesday that local fire officials had asked for help from ATF because of the "size and scope" of the Annapolis mansion fire. He added that the property was a "complete loss."

CNN reported of sources at the bureau saying that the Annapolis mansion fire engulfed the home so quickly that they are suspecting chemicals could have been used to accelerate the burning.

According to Special Agent William McMullan, specialists from across the country were already headed to Annapolis, whilst also sending in trained dogs to sniff out any traces of accelerant chemicals to determine whether the blaze was deliberate.

Most of the Annapolis mansion fire seems to have been already extinguished by late Monday morning. However, some firefighters were reportedly still pouring water by midday, almost nine hours after the fire began, according to Mail Online. Fire chiefs also weren't able to search the house during the blaze, therefore it is unlikely that victims of the Annapolis mansion fire will be confirmed until later today.