A purported al Qaeda statement, posted late Saturday on an Islamic Web site, included a passport-size photo of Paul Johnson Jr. and a Lockheed Martin business card bearing his name. The statement threatened to treat Johnson as U.S. troops treated Iraqi prisoners — an apparent reference to abuses at Abu Ghraib prison in Iraq.
According to a translation by CBS News, the demands include the arrest of several Saudi officials for theft, "treason" and violating Islamic law; the release of militants from jail; the dismissal of judges; the publication of "the accounts of state"; and the expulsion of the U.S. ambassador.
Al Qaeda, led by Saudi-born Osama bin Laden, often rails against Saudi Arabia's rulers for their close links to the United States.
"All the editors of the local newspapers must be dismissed and put on trial for lying and deception," the demands state. "All the Lebanese journalists must be dismissed from the local newspapers."
One of the 13 demands singles out "the apostatizing author Turki Al-Hamad" for arrest and trial for "insulting the divine entity."
Al-Hamad is the author of the book Adama, the fictional account of a boy's disenchantment with Arab nationalism. The book has been banned in several Islamic countries.
Johnson's family in New Jersey was devastated by the news of his kidnapping, said Barbara Pagliughi, a home health aide for his 67-year-old mother.
"They don't know what's going on. They learned through the media," Pagliughi said. "Nobody came and contacted them. Nobody knows where he is, whether he's alive, if they've tortured him."
Johnson's son, Paul Johnson III, told NBC he planned to head to New Jersey where his father's brother and sister also live.
"Let him go," Johnson III said, addressing the captors from his home in Florida's Space Coast where friends placed yellow ribbons on trees in the front yard. "It's not his fault we're over there. It's not his fault we had to go there. It was his job."
Johnson, 49, worked on the radar systems of Apache helicopters and had been scheduled to come back to the United States in June. However, the vacation was pushed back until the fall.
Lockheed Martin released a statement Sunday that said: "We believe he has been kidnapped, but we have no information on his status or whereabouts. We will continue to work with U.S. and Saudi government and military officials and the family of Mr. Johnson to provide any assistance possible. Our thoughts and prayers are with Paul Johnson and his family."
In Stafford Township, Johnson's mother, Delores, and brother, Wayne, awaited word.
"I just don't want to hear bad news because I know they're sadistic," said Wayne Johnson, 48. "The more people know about it then maybe they can get him out safe."
Paul Johnson Jr., a former Air Force servicemember, moved from New Jersey to Florida in the early 1980s to work for Lockheed Martin. He had worked in Saudi Arabia for more than a decade.
"My father — has always been nervous about being there," Paul Johnson III told NBC. "But over the years of being there, you pump your gas at the same place. You get your coffee at the same place. You just get into routines and I think that's just what happened to him."
Three Westerners have been killed in the Saudi capital in a week, including Robert Jacobs, of Murphysboro, Ill., who was killed in his parking garage Tuesday. Several Islamic Web sites were carrying links to a videotape — purportedly from al Qaeda — that claims to show Jacobs being killed.
The militant attacks against Westerners, government targets and economic interests in the kingdom have surged despite a high-profile campaign against terrorists the government began after suicide bombings last year.
Terror experts have noted that the militants are using several tactics — including shootings and ambushes where the gunmen do not die — rather than limiting themselves to suicide bombings or swift attacks under the cover of darkness.
The U.S. Embassy warned that the attacks appeared to follow extensive surveillance of the two Americans slain over the past week.
The militants are clearly spreading fear in the oil kingdom. In the huge expatriate community, there are some 35,000 American citizens. The U.S. Embassy had already advised Americans to leave the kingdom, and the British Embassy on Sunday said it was authorizing the voluntary departure of nonessential staff and their families.
Saudi Arabia relies heavily on a foreign work force. An estimated 8.8 million foreigners work among 17 million Saudis in the kingdom, some in the oil sector, banking and other high-level businesses, but the majority in service-industry jobs such as maids, bellboys or taxi drivers.
"They have a program, those militants - and they want to 'Talibanize' Saudi Arabia - and they will not be allowed to do so," says Jamal Khashoggi, a spokesman for the Saudi ambassador in London.
Crown Prince Abdullah made a public pledge the militants won't escape justice. However, since last month's killing of 22 foreigners at an oil industry complex, gunmen have also killed a BBC cameraman and critically wounded a correspondent. And the Saudis' most-wanted list is only getting longer.
Saudi security officials, speaking on condition of anonymity, said police stormed a suburban Riyadh house Sunday morning, arresting a man inside and confiscating a computer. It wasn't clear whether he was linked to any of the past week's shootings.