Investigators found the bodies of two more people in the charred remains of an Annapolis-area mansion that burned to the ground earlier this week, bringing the number of dead to four.

Crews found two bodies on Thursday, the second day of excavating the site, and two bodies on Wednesday, according to Anne Arundel County Fire Department spokesman Capt. Russ Davies.

Six people — Don and Sandra Pyle and their four grandchildren — had been unaccounted for since a massive fire reduced a 16,000-square-foot waterfront mansion near the state's capital to rubble early Monday.

Relatives said after the blaze that they believed the Pyles and their grandchildren were all inside the mansion when it caught fire.

Investigators would not say whether the bodies found were those of adults or children, only that they are being sent to the Office of the State Medical Examiner in Baltimore for identification.

Family members of the Pyles said in a statement Thursday that they are grateful for the love and support they have received in the wake of the fire, and identified the four children they believe were killed as two sets of siblings, all between 6 and 8 years old.

Fire officials said the fire spread quickly through the 7-bedroom, 7-and-a-half bath mansion. Investigators said the home did not have a sprinkler system.

Federal investigators from the U.S. Department of Alcohol, Tobacco, Firearms and Explosives are assisting with the investigation.

A cause of the blaze has not yet been determined.