DHAHRAN, Saudi Arabia (AP) _ Twenty-eight journalists from American, British, French and Italian news organizations have disappeared while traveling in southern Iraq, officials and their agencies said today.

The U.S. Central Command said 11 journalists for American, British and Italian agencies or newspapers were ''believed to be in serious danger.''

In Paris, the French Foreign Ministry said 15 French journalists have been missing in southern Iraq for three days. One of the Frenchmen works for a British news agency and was included in the 11 reported by the U.S. command.

A three-man British crew from Independent Television News also was missing in southern Iraq, an ITN correspondent in Dhahran reported. He asked that their names be withheld until relatives could be notified. The three-man crew has headed toward Basra on Sunday, he said.

The U.S. command said the 11 journalists left Kuwait on Sunday afternoon without a military escort and headed toward Basra in southern Iraq. They failed to return on Monday as scheduled, it said.

The Basra area has been reported in the midst of serious turmoil. Violent clashes have been described there and in other regions of Iraq between supporters and opponents of President Saddam Hussein.

The U.S. command said the reporters and photographers were believed to have passed through a U.S. military checkpoint at the Kuwait-Iraq border and then traveled along the road north to Basra, Iraq's second-largest city. They were last seen about 25 miles south of Basra on Monday.

The French reporters have not been heard from since Sunday, ministry spokesman Maurice Gourdault-Montagne said. ''Their disappearance worries us greatly,'' he said.

Associated Press photographers Don Mell and Scott Applewhite, who traveled about 15 miles into Iraq on Saturday along the road leading from the Kuwaiti border, said they were warned it was dangerous to proceed farther.

''Both the civilians and the soldiers that we came into contact with seemed very concerned for our personal safety,'' said Mell.

He said at one point, a small pickup truck carrying Iraqi civilians stopped them just south of the town of al-Zubayr.

''The driver got out and told us not to proceed to al-Zubayr or any other point farther up the road'' because the Republican Guards and Iraq's secret police, were ''operating in the area and would shoot us.''

Mell, a veteran of Beirut and other Middle East conflicts, said he and Applewhite turned back toward Kuwait.

The U.S. command and the Italian Foreign Ministry identified nine of the the 11 missing journalists as Neal Conan of National Public Radio; Chris Hedges of The New York Times; Philippe Wojazer and Santiago Lyon, photographers with the Reuters news agency; Greg Lamotte and Tyrone Edwards of Cable News Network; Gabriella Simoni, of Italy's Canale Cinque television; Giovanni Porzio of the Italian news magazine, Panorama; and Lorenzo Bianchi, of the Resto del Carlino newspaper. The names and nationalities of the other two journalists who left Kuwait on Sunday were not immediately known.

The French Foreign Ministry identified the missing French journalists as Wojazer of Reuters; Patrick Bourrat, Bruce Frankel, Francois Dore and Patrick Michel of TF1 television; Gilles Trenel, Herve Brusini, Franck Brisset and Jacques Gauthier of Antenne-2 television; Loic Madeline and Pascal Richard of La Cinq television; Francoise Chipaux of Le Monde; Francois Came of Liberation; Francois Landon of L'Evenement du Jeudi; and Pierre Thebault of Radio Monte Carlo.