MORONI: A second child may have survived the Comoros jet crash and a hospital on the main island in the Indian Ocean archipelago was put on alert Wednesday to treat the victim, doctors said.

But the French Cooperation Minister Alain Joyandet immediately denied the reports.

"I want to deny this report... This is false information," Joyandet told France Info radio from the Comoros, where he flew on Tuesday to help rescue efforts.

He said the only survivor from the 153 people aboard a Yemenia Airlines jet that plunged into the sea early Tuesday was a 13-year-old girl who clung to floating wreckage.

"There is no other survivor," the minister said.

A doctor in Moroni earlier said a second child may have survived and that a hospital was put on alert to receive the victim.

"It seems that another child was found alive early in the morning. We have no detail on the victim because we have not seen him," said the doctor at El Maarouf hospital who spoke on condition of anonymity.

He said the child may still be with rescuers at sea.

Another doctor confirmed the preparations and criticised the search operation.

"If we find a survivor today, it means he was alive yesterday. The search has not been conducted properly."

Joyandet, who told reporters in Moroni earlier that "there are still chances of finding more survivors," said France was planning to evacuate the teenager, Bahia Bakari.

"France wants to evacuate the young girl and see how to help her father who wants to travel to the Comoros to find his wife's body," he said, adding that "the priority is to evacuate the young girl."

"Physically she is fine... She clung to a piece of debris," said Joyandet who arrived in the former French colony early Wednesday.

Visits to the Comoros main El Maarouf hospital where she was taken for treatement have been restricted.

Bakari was travelling with her mother from the southern French city of Marseille.