The tickets for two passengers who used stolen passports to travel on a missing Malaysia Airlines flight were booked by an Iranian man known only as “Mr. Ali,” Britain’s Financial Times reported Monday, as the search for the jet, which vanished Saturday with 239 people on board, was significantly expanded.

A Thai travel agent, who arranged the tickets on flight MH370 from Kuala Lumpur to Beijing for the pair, said an Iranian contact she had known for three years asked her to make the bookings. She said the two, who used Italian and Austrian passports that later turned out to have been stolen, had been booked to board a connecting flight together to Amsterdam.

Authorities investigating the plane’s disappearance have not ruled out terrorism.

The travel agent, Benjaporn Krutnait, owner of the Grand Horizon travel agency in Pattaya, told the Financial Times that the Iranian man, who she said was a business contact she knew only as Mr. Ali, had initially asked her to book cheap flights to Europe for the pair on March 1. Those tickets expired. “When he contacted her again on Thursday, she rebooked the men on the Malaysia Airlines flight through Beijing because it was the cheapest available,” the report said.

The agent said a friend of Mr. Ali paid for the tickets in cash, and speculated that Mr Ali might have been a middleman, booking tickets for others in exchange for a commission, the British newspaper said.

Supachai Phuikaewkhum, the chief of police in Pattaya, said that Mr. Ali’s friend was also an Iranian, and was questioned on Monday, the New York Times reported.

The Financial Times said it could not reach Mr. Ali on a Tehran mobile phone number provided by the travel agent. It stressed there was no evidence that Mr. Ali knew the two men were using stolen passports.

“Ms. Benjaporn said she did not believe Mr. Ali was linked to terrorism,” the paper reported, “particularly as he had not specified booking the Kuala Lumpur-Beijing flight but had instead asked for the cheapest route to Europe. Ms Benjaporn said she was speaking about the case because she was concerned over the speculation about a terrorist attack and wanted the facts to be known.”

Two European names — Christian Kozel, an Austrian, and Luigi Maraldi of Italy — were listed on the flight manifest, but neither man boarded the plane.

Both had their passports stolen in Thailand in the last two years and questions swirled over how the two passengers using their documents managed to board the flight.

Malaysia’s police chief was quoted by local media as saying that one of the two passengers had been identified — something that could speed up the investigation. Civil aviation chief Azharuddin Abdul Rahman declined to confirm this, but said the two passengers were of “non-Asian” appearance, adding that authorities were looking at the possibility the men were connected to a stolen passport syndicate.

Asked by a reporter what they looked like, he said: “Do you know of a footballer by the name of (Mario) Balotelli? He is an Italian. Do you know how he looks like?” A reporter then asked, “Is he black?” and the aviation chief replied, “Yes.”

This photo taken Dec. 26, 2011, shows the Malaysia Airlines Boeing 777-200ER that disappeared from air traffic control screens Saturday, taking off from Roissy-Charles de Gaulle Airport in France. The Malaysia Airlines Boeing 777-200 carrying 239 people lost contact with air traffic control early Saturday morning, March 8, 2014 on a flight from Kuala Lumpur to Beijing, and international aviation authorities still hadn't located the jetliner several hours later. (photo credit: AP/Laurent Errera)

This photo taken Dec. 26, 2011, shows the Malaysia Airlines Boeing 777-200ER that disappeared from air traffic control screens Saturday, taking off from Roissy-Charles de Gaulle Airport in France. The Malaysia Airlines Boeing 777-200 carrying 239 people lost contact with air traffic control early Saturday morning, March 8, 2014 on a flight from Kuala Lumpur to Beijing, and international aviation authorities still hadn’t located the jetliner several hours later. (photo credit: AP/Laurent Errera)

Malaysian authorities have widened their search for the plane. The initial zone spread over a 50 nautical miles (92 kilometers) radius around the point where flight MH370 disappeared over the South China Sea in the early hours of Saturday morning. On Monday, that search zone was doubled to 100 nautical miles. “The area of search has been expanded in the South China Sea,” Civil Aviation Department chief Azharuddin told reporters late Monday.

He also confirmed the search area covers land on the Malaysian peninsula itself, the waters off its west coast and an area to the north of the Indonesian island of Sumatra.

The huge area now being covered reflects authorities’ bafflement over the disappearance of the flight, with 40 ships and more than 30 planes finding no sign of it.

Emotions are running high as Beijing blamed Kuala Lumpur for a lack of information, while tearful relatives of the 153 Chinese passengers aboard voiced frustration with all sides of the response effort.

China said Malaysia needed to “step up” its efforts after authorities admitted they were mystified.

“The Malaysian side cannot shirk its responsibilities,” the Global Times newspaper, which is close to the ruling Communist Party, wrote in a scathing editorial. “The initial response from Malaysia was not swift enough.”

A day of conflicting information deepened relatives’ anguish, with tests on oil slicks in the South China Sea showing they were not from the Boeing 777 and reports of possible debris from the flight proving to be false alarms.

Hong Kong’s Civil Aviation Department said that a pilot on a flight from the southern Chinese city to Kuala Lumpur had reported seeing “large debris” while flying over Vietnamese waters in the latest sighting to be investigated.

The United States has sent an FBI team to help investigate the passengers, but US officials stressed there was as yet no evidence of terrorism.

Malaysia’s police chief said Monday one of the passengers traveling with a stolen passport had been identified, but gave no further details.

Azharuddin said that the two men were not of Asian appearance, contrary to previous reports.

But he had few answers to the burning questions over the missing plane.

Asked whether it was possible the plane had been hijacked or disintegrated mid-air, he said nothing could be ruled out.

“We are looking at every aspect of what could have happened,” he said.

“This unprecedented missing aircraft mystery — it is mystifying and we are increasing our efforts to do what we have to do.”

At a Beijing hotel, Malaysian embassy officials were processing visa applications for families wanting to take up an offer from MAS to travel to Kuala Lumpur to be closer to the rescue operations.

Scores of relatives made their way into the room, some in groups of five or six, clutching handkerchiefs and wiping away tears from their faces.

Others said they would not go. “There is more we can do here in China,” one woman told AFP. “They haven’t even found the plane yet.”

A team of Chinese officials from government ministries headed for Malaysia on Monday, tasked with investigating the incident and helping family members already there.

As the search entered a third full day, other families of missing passengers gathered at a hotel in Malaysia’s administrative capital, Putrajaya, sharing breakfast as they stared intently at television news bulletins.

Malaysian officials have said there was a possibility that MH370 may have inexplicably turned back towards Kuala Lumpur.

The plane, captained by a veteran MAS pilot, had relayed no indications of distress, and weather at the time was said to be good.

AP contributed to this report.