(CBS/AP) - The so far fruitless search for Malaysia Airlines Flight 370 continues, almost seven weeks after the plane disappeared while it was mid-flight from Kuala Lumpur to Beijing with 239 people aboard.
Here are this week's developments in the baffling mystery, as investigators plumbed the ocean depths off the coast of Australia.
1. Malaysia's prime minister, Najib Razak, said his government was not prepared to declare the plane lost.
"At some point in time I would be, but right now I think I need to take into account the feelings of the next of kin -- and some of them have said publicly that they aren't willing to accept it until they find hard evidence," Razak told CNN.
Nonetheless he said it was "hard to imagine otherwise."
Last month, Razak announced at a news conference that the flight had ended in the southern Indian Ocean.
2. Families frustrated by the lack of answers from Malaysian authorities plan to take their questions directly to the plane's maker, according to the partner of one of the passengers.
Sarah Bajc, the girlfriend of American Philip Wood, told CNN that relatives would direct their questions to Boeing, which has a shareholders meeting next week.
"And if we're not getting information directly from Malaysia Airlines and from the Malaysian government, we might as well try to go directly to the source," she said.
"Boeing is a publicly traded company in the United States, and that puts them in a position of a little bit more fiduciary responsibility," she said.
Bajc also accused the Malaysian authorities of treating the families as if they were the enemy.
3. Debris that washed ashore on a western Australian beach does not appear to be from the missing plane, according to Australian officials.
Martin Dolan, chief commissioner of the Australian Transport Safety Bureau, said an initial analysis of the material suggested it was not from Flight 370.
"We do not consider this likely to be of use to our search for MH370," Dolan told The Associated Press. "At this stage, we are not getting excited."
No debris from the plane has been identified.
4. More than 90 percent of the remote stretch of the Indian Ocean where the plane is thought to have crashed has been scanned, according to the Joint Agency Coordination Centre, which is overseeing the search.
A robotic submarine, the U.S. Navy's Bluefin 21, is searching 120 square miles far off Australia's west coast, but nothing of interest had been found. The submarine is creating a three-dimensional sonar map of the ocean floor near where signals consistent with airplane black boxes were heard.
5. What's next in the long search?
The next phase will likely be decided in a week and involve using more powerful, towed side-scan commercial sonar equipment, similar to the equipment that found the Titanic wreck in 1985.