Egyptian state television on Friday interrupted a soap opera to announce that the director-general of the UN nuclear agency had won the Nobel together with the organisation.
With understandable pride, the news presenter said ElBaradei was the fourth Egyptian to win a Nobel. Ahmed Zewail won the chemistry prize in 1999; Naguib Mahfouz won the literature prize in 1988; and the late president Anwar Sadat won the peace prize in 1979.
ElBaradei's mother, Aida Hegazi, told state television: "God rewarded him for his hard work. It brings great happiness to him and to us."
In a phone call from her home in Dokki, Giza, the twin city of Cairo, she said: "He's a man who has worked with sincerity - anything he does, he does with sincerity."
She revealed she is close to her son, although he spends only two to four weeks in Egypt a year. "His brothers used to describe him as my adviser," she said.
Day of pride
There was no immediate comment from the government as Friday is the Muslim weekend in Egypt, but the television ran an interview with the country's ambassador to Austria, Ramzy Ezz Eldin, who said it was "a day of pride for all Egyptians".
"It is very important for an Arab and a Muslim to get this prize at this moment - a time when the image of Arabs and Muslims is in ruins," Ezz Eldin said.
ElBaradei was unknown in Egypt
until three or four years ago
In Vienna, where the IAEA is based, ElBaradei, said he was "extremely humbled and honoured".
"The award sends a very strong message: 'Keep doing what you are doing - be impartial, act with integrity,' and that is what we intend to do," ElBaradei said after applause from UN staff.
"The advantage of having this recognition today, it will strengthen my resolve.
"The fact that there is overwhelming public support for our work definitely will help to resolve some of the major outstanding issues we are facing today, including North Korea, including Iran and nuclear disarmament.
"It is a responsibility but it is also a shot in the arm."
Traditional phone call
ElBaradei said he had been certain he would not win, despite being favoured, because he had not received the traditional advance telephone call from the Nobel committee. He only learned of his win while watching the televised ceremony.
"This came as an absolute surprise to me," he said.
"I was watching television with my wife at 11 o'clock fully aware that we did not make it because I did not get the call.
"And then I heard in Norwegian the [IAEA] and my name" and "I was just on my feet with my wife, hugging and kissing and full of joy and full of pride," he said.
The Nobel committee said before the announcement it had tightened secrecy after Reuters published the names of the 2003 and 2004 winners before the official announcements.
ElBaradei has faced criticism from many quarters, most recently from the US and Iran, over his efforts to investigate Tehran's nuclear programme.
"I was just on my feet with my wife, hugging and kissing and full of joy and full of pride"
Despite that, he said he had had a pleasant conversation with US Secretary of State Condoleezza Rice.
"Just before coming here, I had a very wonderful talk with Secretary Rice, who wished me well and we agree that we will have to continue to work together."
In Egypt, ElBaradei was unknown until three or four years ago when, as IAEA chief, he became involved in the international debate over whether the then Iraqi president Saddam Hussein had weapons of mass destruction.
Trained as a lawyer, ElBaradei had made his career abroad. Born in Cairo in 1942, ElBaradei earned a bachelor's degree in law in 1962 at the University of Cairo.
After a stint in the Egyptian Ministry of Foreign Affairs, he received a doctorate in international law at the New York University School of Law in 1974, and later taught there.
He joined the IAEA in 1984 and rose to the top of the organisation. He is married with two children.
Late Egyptian president Anwar
Sadat won the Nobel in 1979
The previous Egyptian winner Zewail won the chemistry Nobel for developing femtochemistry, which enables scientists to see how atoms move during chemical reactions in slow motion.
Mahfouz, who was born in 1911, is the only Arabic writer to have won the literature Nobel. The award committee credited him with creating "an Arabian narrative art that applies to all mankind".
Sadat won the peace Nobel for negotiating the Arab world's first peace treaty with Israel. His co-winner was the Israeli Prime Minister Menachem Begin.
In 1981, two years after the treaty was signed on the White House lawn, Sadat was assassinated by Islamists opposed to peace with Israel.