UNITED NATIONS, Nov. 10 (Xinhua) -- Preliminary tests have shown that the mysterious white powder contained in envelopes sent to three UN missions in New York is not dangerous, said Austria's UN Ambassador Thomas Mayr-Harting on Tuesday.

    Mayr-Harting, whose country holds the UN Security Council's rotating presidency for this month, told reporters at the UN Headquarters that the substance is still being examined by the authorities.

    "The preliminary findings we received is that they were not dangerous, but evidently we are waiting for a definite answer," he said.

    The work of the mission is "returning back to normal," he said.

    Mayr-Harting declined to confirm whether a text message was conveyed in the letter along with the white powder.

    "As soon as it was clear that there was powder in this envelope, the envelopes were taken away by police authorities," he said.

    The mysterious white substance, which evoked memories of the 2001 anthrax attacks, was delivered to the permanent missions of Austria, France and Uzbekistan to the UN in midtown Manhattan on Monday.