Charles 'Chuck' Robb, 82, and Lynda Robb, 77, were injured when the blaze engulfed the luxury property in northern Virginia.

Dramatic pictures showed firefighters battling to extinguish the inferno as it ripped through the mansion, located in the luxury 600 block of the Chain Bridge Road development in McLean - home to several wealthy political figures.

Mr Robb, who served as Virginia governor from 1982 to 1986, and as senator from 1989 to 2001, was treated for smoke inhalation and later discharged from hospital.

Mrs Robb, daughter of former US president Lyndon Johnson, continues to receive treatment for second-degree burns and smoke inhalation, a family member said.

The property, which the Robbs have lived in for almost 50 years, has suffered "major damage".

The couple, who have three daughters, were the only people at home when the blaze broke out around 11.30pm on Tuesday night.

In a joint statement, the siblings said: "Our entire family is deeply grateful to the firefighters for their rapid response and the medical professionals who are taking care of them.

"We have what is most important to us - our mom and dad."

Fairfax County Fire and Rescue Department shared pictures and footage of the scene on Twitter.

They posted: "Two persons transported to hospital with non-life-threatening injuries."

In a series of updates they said the blaze had been brought under control, showing the charred remains of the mansion.

Several nearby apartments have been "displaced" with investigators now trying to establish the cause of the fire.

"Based on the severity of the fire it could take days/weeks," another tweet said.

The current state governor, Ralph Northam, has extended his sympathies to the Robbs.

He said he and wife Pam were "deeply saddened" at the news of the fire, adding: "Our thoughts are with Chuck and Lynda as they recover from this tragedy."

Tax records show the home has a value of $5.5m (£4.1m).