India lost contact with its unmanned spacecraft just before it was due to land on the Moon on Saturday in a blow to the country's ambitious low-cost lunar programme.
India had hoped to become just the fourth country after the United States, Russia and China to successfully land on the Moon.
But as Prime Minister Narendra Modi looked on, the mood in mission control in the southern city of Bangalore soon deteriorated when it became clear that everything was not going according to plan.
After several tense minutes as the expected landing time came and went, Indian Space Research Organisation (ISRO) chairman Kailasavadivoo Sivan announced that communication with the lander had been lost.
"The 'Vikram' lander descent was (going) as planned and normal performance was observed," until the craft had descended to 2.1km above the South Pole region, Sivan said.
"Subsequently the communication from the lander to the ground station was lost. The data is being analysed," he said, surrounded by grim-faced engineers and technicians in the control room.
Modi told them after Sivan's announcement that "what you have done (already) is not a small achievement".
The prime minister was due to address the nation at 8am local time.