CANBERRA, Australia (AP) — Officials plan to search deeper in the Indian Ocean for Malaysia Airlines Flight 370, which disappeared March 8.

Australia's prime minister says officials plan to bring in more powerful sonar equipment that can delve deeper beneath the ocean.

A U.S. Navy robotic sub has scanned most of the 120-square-mile area it's supposed to cover, but as of yet, officials say it's found nothing related to the plane.

Meanwhile, unidentified material that's washed ashore in southwestern Australia is being examined.

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