Calum MacLeod

USA TODAY

BEIJING — Relatives of passengers on Malaysia Airlines Flight 370 are launching a crowd-funding campaign to raise a $3 million reward for a whistle-blower to expose key information about the vanished jetliner, the partner of a missing passenger told USA TODAY.

A $2 million fund for private investigators to follow up on promising leads is also being targeted.

Almost three months after the plane disappeared en route from Kuala Lumpur to Beijing, some relatives are frustrated by the failure of the official search to find concrete evidence about what happened and in what manner, and they say they are convinced that authorities are concealing the truth.

"We are taking matters into our own hands," said Sarah Bajc, a U.S. citizen whose partner, Philip Wood, 50, an IBM executive from Texas, was on the flight when it disappeared March 8. "There is no credible evidence" the plane is in the southern Indian Ocean, where planes, boats and a mini-sub have searched in vain for weeks, she said.

"I'm convinced that somebody is concealing something," said Bajc, 48, a business studies teacher in Beijing and former executive with Microsoft.

The head of the Australian joint agency overseeing the search rejected the families' claims. "Nothing important is being concealed in any way," said Angus Houston, a former air chief marshal of Australia. "My approach has always been to be as open as I could possibly be," he told USA TODAY.

"Is every piece of analysis out there? I don't think it is," said Houston, who hopes to announce this month the completion of a comprehensive review of all data pertaining to the search. "But the analysis is still ongoing," he added Friday.

Meanwhile, Malaysia's acting transport minister, Hishammuddin Hussein, has said that "requests made by next-of-kin and international media cannot be accommodated 100%."

Called Reward MH370: The Search for the Truth, the campaign by families to raise money will launch Monday on the crowd-funding website Indiegogo. The minimum donation will be $5. The relatives got permission from Indiegogo to raise money for a reward, which the firm has not previously permitted, Bajc said.

Of the $5 million sought, $3 million will be put up to reward a whistle-blower for coming forward. The campaign will hire a professional company licensed to operate in multiple countries. Bajc expects its work to include securing court orders, such as to pull cellphone tower records from underneath the flight path.

The campaign is an initiative of family members from the USA, Australia, New Zealand, France and India, Bajc said, and does not involve relatives of passengers from China or Malaysia, whose citizens formed the majority of those on the flight.

"Granted, $2 million in investigation services won't go very far," Bajc acknowledged. "Clearly, they've already spent $100 million, and they've gotten nothing. But we're not going to approach it with boats in the ocean. We're going to approach it with human intelligence."

Potential donors should understand that "there are no promises here, but we believe we need to try something. If we just sit back on our heels and allow the existing path to continue, I don't think this will ever be solved," she said.

The relatives hope they turn up "a whistle-blower who says, 'I know where to find this' " or a flight controller who can access new data, but they expect they will also encounter "some unethical people," Bajc said. "I don't care. I just want to find the plane."

Malaysian officials have repeatedly insisted that the investigation has been fully transparent and that the raw data surrounding the investigation are complex and difficult to explain.

Australian transportation authorities will hire a specialist company to begin a renewed underwater search in a revised search zone in August. A Chinese ship is conducting underwater mapping of the ocean floor to assist the later search. The U.S. Navy's mini-sub Bluefin-21 is no longer being used.

"If there was any evidence that that plane was wrecked in the water, even a seat cushion, I would be taking a totally different approach," Bajc said. "But there's been nothing."