The jet bound for the Kenyan capital, Nairobi, went down near the town of Lolodorf, about 155 miles south of the coastal city of Douala, where it had taken off after midnight, said Alex Bayeck, a regional communications officer.
The Boeing 737-800 was carrying 114 people, including 105 passengers, from at least 23 countries, Kenyan airline officials said. A Nairobi-based Associated Press correspondent, Anthony Mitchell, was believed to be among the passengers. Mitchell had been on assignment in the region for the past week.
Kathleen Carroll, the AP executive editor, said Mitchell "contacted his family before boarding the flight to let them know he was headed home."
"We hope for the best," she said.
[In recent weeks, Mitchell had covered fighting in Somalia, rapes in Darfur, and other subjects in the region.]
There was no word on survivors, said Bayeck, speaking by telephone en route to the crash site. He said search planes were flying over the forested area where the airliner gave off a distress signal, but no wreckage had been spotted.
He said residents in the area, which has few roads and is dotted by small villages, reported hearing a "large boom" during the night. "Searchers have gone out looking in this area," he said.
Kenya Airways CEO Titus Naikuni said the plane, which was almost new, took off an hour late because of rain. He said the distress call was issued automatically _ "from a machine, not a pilot."
Kenya's transport minister, Ali Chirau Makwere, said it was too early to determine what caused the crash.
"We need to get information from the technical experts as to whether it was occasioned by the weather or pilot error or mechanical fault," he said in Nairobi. "We really don't know. It's too early to make any conclusions."
Relatives waiting at Nairobi's airport began wailing as news reports of the crash filtered in. Dozens of family members collapsed in the airport terminal.
Janet Mwema said she believed her daughter, Vicky, a cabin crew member, might have been on the flight but said counselors could not confirm that for her.
"We trust God that he will strengthen his people," Mwema said. "Because we all go one day, whether it is accident or what."
The flight departed Douala at 12:05 a.m. and was to have arrive in Nairobi at 6:15 a.m. The flight originated in Ivory Coast but stopped in Cameroon to pick up more passengers, the airline said.
"The last message was received in Douala after takeoff and thereafter the tower was unable to contact the plane," Kenya Airways' Naikuni said earlier Saturday.
The Douala-Nairobi flight runs several times a week, and is commonly used as an intermediary flight to Europe and the Middle East.
Kenya Airways -- considered one of the safest airlines in Africa -- said most passengers were planning to transfer to ongoing flights in Nairobi.
Naikuni said the plane was only six months old.
U.S. aviation officials are standing by, expecting to head to Cameroon and help with the investigation if asked.
"Generally, other governments don't have the same accident investigation expertise that we have," said Laura Brown, a spokeswoman for the Federal Aviation Administration.
In 2004, the United States helped investigate the crash of a Flash Airlines Boeing 737 that killed all 148 on board minutes after taking off from the Red Sea resort of Sharm el-Sheik, Egypt.
Boeing spokesman Jim Proulx said there have not been any safety concerns with the Chicago-based company's fleet of 737-800s. About 2,000 737-800s are in use around the world.
"We express our profound concern for the passengers and crew on board on the Kenyan Airways flight that went missing," Proulx said Saturday. "We stand ready to assist the authorities if they ask us to do so."
The last crash of an international Kenya Airways flight was on Jan. 30, 2000, when Flight 431 was taking off from Abidjan, Ivory Coast, on its way to Nairobi. Investigators blamed a faulty alarm and pilot error for that crash, which killed 169 people.
Associated Press writers Elizabeth A. Kennedy and Tom Maliti contributed to this report from Nairobi, Kenya.
By: A Kenya Airways jet with 114 people on board crashed early Saturday after sending out a distress signal over a remote rainforest in southern Cameroon, officials said. Nearby villagers reported hearing a loud boom.