PHNOM PENH, Cambodia - As a suspension bridge in the Cambodian capital swayed under the weight of thousands of revellers, some began to shout that the structure was going to collapse. Others pushed, heaved and even jumped off the span as a panic took hold that ended in the deaths of more than 350 people.

Though typical, the movement of the bridge terrified the festival goers -- many of whom were in Phnom Penh from the provinces for the end of rainy season and were unfamiliar with such bridges, city police Chief Touch Naroth said Wednesday, citing a government investigation he took part in.

"People became panicked when they saw other people fall down, and they started running when they heard cries that the bridge was going to collapse," Touch Naroth told AP Television News. The police chief shared details of the probe, though an official report has not been released.

Information Minister Khieu Kanharith said Wednesday the official death toll was 351 dead with 395 injured.

But casualty figures have been a matter of confusion, with officials saying Tuesday that at least 755 people were hurt before walking that number back.

The Ministry of Social Welfare, for instance, is now citing two death tolls: one, based on data collected from hospitals in the capital, that is similar to the official figure, and another -- 456 -- based on reports collected from provincial officials.

The discrepancy could stem from the fact that friends or relatives took victims' bodies home before their deaths could be registered.

Prime Minister Hun Sen described the stampede as the biggest tragedy since the communist Khmer Rouge's reign of terror, which killed an estimated 1.7 million people in the late 1970s. He declared a day of national mourning for Thursday.

As many as two million people are believed to have come to the capital for celebrations of a three-day holiday marking the end of the monsoon season. As festivities wrapped up Monday night, tens of thousands flocked to a free concert on an island in the Bassac river.

An estimated 7,000 to 8,000 people were streaming over a bridge that connects the island to the mainland when it began to sway, according to Banyon TV, which serves as a mouthpiece for the government and was citing the investigation committee.

Thousands of Cambodians on Wednesday lit candles and made offerings to appease the souls of those who perished.

"I asked their souls to rest in peace and not to be angry with those still alive in the capital, especially my family members and relatives," said Meng Houth, a 52-year-old woman who laid out food and burned incense and a candle in front of her home.

Street cleaners late Wednesday removed the debris that littered the yellow-and-grey bridge after the disaster: rubber sandals and other footwear, plastic bracelets, water bottles, condom wrappers and pieces of sugar cane pieces, a local snack. Hun Sen was expected to pay a visit to the scene Thursday morning.

For Thursday's day of national mourning, the Tourism Ministry has asked all entertainment venues, including karaoke parlours, nightclubs, beer gardens and discotheques, to close for the day.