BEIJING (AFP) - A spectacular fire on Monday night engulfed a hotel building in the uncompleted CCTV headquarters complex, one of the icons of Beijing's high-tech architectural rebirth, an AFP witness said. State Xinhua news agency said the blaze was in a Mandarin Oriental Hotel due to open later this year within the complex housing the future headquarters of China Central Television, the country's state television broadcaster. The 159-metre building that caught fire was a few hundred metres from the showpiece 234-metre main headquarters tower structure. The tower did not appear to be threatened by the blaze, the AFP journalist at the scene said. Xinhua said there was no immediate word on casualties. However, it quoted witnesses saying some lights had been seen on inside the burning building. The fire sent flames and billowing clouds of sparks shooting high into the night sky over the eastern portion of the Chinese capital, drawing thousands of picture-snapping spectators. The incident is likely to be an embarrassment for the government, and CCTV itself still had not reported the fire in its future headquarters complex several hours after it first erupted. The complex's main structure has made headlines for its innovative design of two towers leaning inward and locked together in a high-altitude embrace. The fire came amid a final burst of Lunar New Year fireworks marking the end of the holiday, China's most important annual festival, when barrages of pyrotechnics thunder across the country. Xinhua quoted a witness saying the blaze appeared to have been sparked after fireworks landed on top of the hotel building. Police cordoned off streets leading to the area and the wail of sirens echoed through the night as fire engines and other emergency vehicles raced to the scene. The complex is one of several symbols of cutting-edge architecture in Beijing introduced in the run-up to the 2008 Beijing Olympics. They also include the new National Stadium at the centre of the Olympic Green, dubbed the Bird's Nest for its threads of interlocking steel beams, and the National Aquatic Centre, which features an exterior resembling bubbles of water moving over a blue box.