Investigators are looking for a woman who reportedly made a two-minute call to Captain Zaharie Ahmad Shah, 53, from a mobile phone obtained under a false identity.
The mystery woman was the last person to contact the captain before the doomed plane took off.
According to the NY Daily News, the phone's SIM card was traced back to a shop in Kuala Lumpur, where it was bought by someone with a woman's name, who used a false identity.
The find has raised fears that Zaharie had ties to terror groups, who are known to obtain pay-as-you-go phones in a similar way as they are untraceable.
Other people who spoke to the captain before he took off have already been interviewed.
According to the Daily Mail, investigators are now set to question Captain Shah's estranged wife.
The paper reports they have waited two weeks out of respect, but will now formally interview Faizah Khan following pressure from FBI agents assisting the inquiry.
Malaysia Airlines Flight MH370 disappeared on 8 March en route from Kuala Lumpur to Beijing with 239 people on board.
Officials believe the plane was deliberately taken off course.
According to the BBC, it is the third set of images in a week of possible debris in the area.
The Australian Maritime Safety Authority (Amsa) is overseeing the search.
A statement published on the Malaysian ministry of transport's Facebook page said: "This morning, Malaysia received new satellite images from the French authorities showing potential objects in the vicinity of the southern corridor.
"Malaysia immediately relayed these images to the Australian rescue co-ordination centre."
Officials described the sighting as being a wooden pallet and a number of other items around it, including some belts of different colours and lengths.
But Mike Barton, operations co-ordinator at Amsa, urged caution, saying the sighting "could be anything".
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