Osama bin Laden
Frame grab from Saudi-owned television network MBC shows Osama bin Laden. Getty Images

Further details are emerging of the plane crash at Blackbushe airport in Hampshire in which Osama bin Laden's stepmother and half-sister are believed to have died. A bin Laden family friend contacted by NBC news named the stepmother as Rajaa Hashim and the half-sister as Sana.

In addition, bin Laden's brother-in-law, Zuhair Hashim, Sana's husband is also thought to be among the four fatalities in the crash.

Police are understood to be investigating the bin Laden family members' presence on the jet, which was flying into Hampshire from Milan. The bin Ladens are believed to have financial interests in northern Italy.

The Brazilia Embraer Phenom 300 crashed shortly after 3pm on 31 July. It was owned by Salem Aviation of Jeddah. The company is named after Osama's eldest brother, Salem, a keen amateur pilot, and it is part of the Bin Laden Group of businesses.

The plane's registration, HZ-IBN, was the same as that used by Osama bin Laden's father, Mohammed bin Awad bin Laden.

In a statement on Twitter, the Saudi ambassador to the UK, Prince Mohammed bin Nawaf Al Saud, offered condolences to the Bin Laden family.

The embassy said it was working with the British authorities to investigate the incident.

The statement said: "His Royal Highness Prince Mohammed bin Nawaf Al Saud has paid his condolences to the family and relatives of Mohammed bin Laden at Blackbushe airport in Britain for the great loss they have suffered as a result of the crash of the plane that was carrying the family."

The embassy added that it was working with the British authorities to ensure the speedy handover of the bodies for funerals and burials in Saudi Arabia.

The bin Laden family has a history of deaths in aircraft crashes.

Mohammed bin Laden was killed in 1967 when he crashed his Beechcraft 18 twin prop plane into a mountain landing strip in Usran, Saudi Arabia.

Salem bin Laden died in San Antonio, USA in 1988 when his light aircraft hit high voltage cables.

The bin Laden family is very extensive. Mohammed bin Awad bin Laden had more than 50 children, including Osama bin Laden. For most of his adult life he had four wives -- the maximum allowed locally under Islamic law -- and he divorced and remarried frequently. He arrived in Saudi Arabia in the early 1930s from Yemen to work on building sites and built up a massive fortune in the construction industry.

Osama bin Laden was killed by US Navy Seals in 2011 in Pakistan.

Meanwhile, more eyewitness accounts of the 31 July crash are emerging. Robert Belcher, an aviation enthusiast, was driving home when he saw a column of black smoke rising from the crash site.

He said: "I was passing the airport on my way home and there was a big column of smoke in the air. The fire service had closed the road behind me.

"I could see the plume of smoke waving from about five miles away and was hoping it was just a car fire rather than an aircraft accident."