Updated

China declared an end Tuesday to the crisis over a brimming lake formed by landslides from a massive earthquake that had threatened flood downstream communities.

Sichuan province's top official, Liu Qibao, claimed a "decisive victory" with water pouring into a manmade spillway from Tangjiashan lake and its level dropped rapidly, the official Xinhua News Agency said.

Liu is Communist Party chief of the southwestern province that was hardest-hit by the May 12 quake that has killed almost 70,000 people.

Towns downstream had been placed on alert for possible flooding in case of an uncontrolled breaching of the lake's unstable banks. But Xinhua said more than half of the 8,800 million cubic feet of water in the lake had been drained off by Tuesday evening, easing pressure on the dam.

Earlier Tuesday, state broadcaster CCTV showed water flowing rapidly out of the lake and flooding low-lying areas of the devastated town of Beichuan just downstream. Residents in the area have long been evacuated and others along the river were preparing to leave if waters rose too high, the station reported.

Flood water seeped into riverside houses in the largely evacuated town of Qinglian, a resident who remained in the area said.

"Everybody feels lucky that it didn't submerge the streets and the neighborhood," said Wu Zhenxing.

In the city of Miangyang, where residents had been practicing evacuation drills, the Fujiang river flowed high and swiftly under a key railway bridge, but stayed within its banks.

For days, troops had been using dynamite and anti-tank weapons to blast boulders and other obstacles in a diversion canal, trying to speed the flow of water and relieve pressure on the lake's unstable mud and rock dam.

More than 250,000 people downstream had moved to high ground due to concerns the barrier holding back the lake could breach entirely. About 1.3 million people total live downstream.

Xinhua said its reporters saw trees, barrels, television sets, refrigerators "and the occasional dead bodies of quake victims" in waters pouring out of the mountains.

Rain was forecast for the Mianyang area Tuesday night, likely raising swells in the area's steep mountain streams.

Also Tuesday, state media said searchers had discovered the wreckage of a helicopter that crashed in deep mountains in southwestern China while ferrying people injured in last month's quake.

The remains of the air force helicopter's five-person crew and 14 quake victims were found at the crash site near the town of Yingxiu, Xinhua said. It said wreckage was spread over a wide area of deep vegetation.

The Russian-designed Mi-171 crashed May 31 near the epicenter of the quake in the Sichuan province town of Wenchuan, after flying into fog and turbulence.

The 7.9 magnitude quake killed 69,146 people, and 17,516 are still missing, according to the government. About 5 million people were made homeless.

Meanwhile, staff at the world's most famous panda reserve on Tuesday buried one of the animals that was killed in a landslide triggered by the quake.

Nine-year-old female Mao Mao was the only panda at the Wolong Giant Panda Reserve confirmed to have died in the quake, said Zhang Hemin, who heads the reserve. The panda's body was found Monday.

Staff placed Mao Mao in a crate, then buried it and placed a large stone on top.

Mao Mao's keeper, He Changgui, sobbed softly as he placed apples and a slice of bread on the stone as a funeral offering.

"I will go back to see her every day," He said.

One other panda, Xiao Xiao, has also been missing since the quake. Forty-seven others still live at Wolong.

The panda is revered in China and serves as an unofficial mascot. About 1,590 pandas live in the wild, mostly in Sichuan and the western province of Shaanxi. An additional 180 have been bred in captivity in hopes of increasing the species' chances of survival.

Earlier, China's security chief stressed the need to maintain order amid a struggle to shelter millions left homeless by the quake and scattered protests over alleged corruption and shoddy school construction.

Zhou Yongkang demanded police and legal staff "solve disputes and help maintain social stability," the Communist Party's official newspaper, The People's Daily, reported Tuesday. Zhou on Monday ended a five-day visit to Sichuan province, where the quake was centered, the paper said.

"A stable social environment is a prerequisite for successful quake relief work," the paper quoted Zhou as saying. The report made no mention of any specific problems.

While there have been no reports of major unrest, refugees have rioted on at least one occasion over misused aid. Parents of children killed in schools have protested to demand officials answer for alleged corruption in the construction process.

At least 15 Sichuan officials have been removed from their posts for mishandling relief work. Another 13 have been given other forms of administrative punishment.