BEIJING (AFP/REUTERS) - Victims of a knife attack in China described attackers dressed in black bursting into a train station in the south-western province of Yunnan and slashing indiscriminately.
The attack on Saturday evening left at least 33 dead and more than 130 wounded, Xinhua said, citing local authorities.
Police shot dead at least four attackers, it said in an earlier report.
A knife victim named Yang Haifei, who was wounded in the chest and back, told Xinhua that he had been buying a train ticket when the attackers approached.
"I saw a person come straight at me with a long knife and I ran away with everyone," he said, while others "simply fell on the ground".
Some who managed to escape were desperately looking for missing loved ones.
"I can't find my husband, and his phone went unanswered," Yang Ziqing was quoted as saying.
She said she had been waiting for her train to Shanghai "when a knife-wielding man suddenly came at them".
Officers sealed off a wide area around the station, it added, while Xinhua said police were questioning people at the site.
The attackers were dressed in similar black clothing, the official China News Service said, citing witnesses.
"A group of men carrying weapons burst into the train station plaza and the ticket hall, stabbing whoever they saw," it said.
A Weibo user going by the name HuangY3xin-Dione who was at a restaurant near the scene told how she saw a group of men in black with two long knives chasing people, Xinhua reported.
Another eyewitness told the Beijing News that she had seen two women in black walking towards the station and that some of the attackers had their faces covered.
Photos posted on Sina Weibo showed blood spattered across the station floor and medical staff crouching over bodies lying on the ground, although the authenticity of the images could not be verified.
The photos showed crowds gathered outside among police officers and ambulances. The injured had been delivered to hospitals around the city, local television station K6 said.
State television showed police wrapping a long, sword-like knife in a plastic bag, amid heavy security at the station.
Weibo users took to the service to describe details of what happened, though many of the posts were quickly deleted by government censors, especially those that described the attackers, two of whom were identified by some as women.
Others condemned the attack.
"No matter who, for whatever reason, or of what race, chose somewhere so crowded as a train station, and made innocent people their target - they are evil and they should go to hell," wrote one user.
State broadcaster CCTV called the incident a "terrorist attack" on its Weibo account.
Xinhua news agency reported on Sunday, quoting the city government, that separatists from China's northwest region of Xinjiang orchestrated the attack.
It said evidence from the scene of the attack pointed to separatists from Xinjiang, a vast region home to the mostly-Muslim Uighur minority.
It is the first time people from Xinjiang have been blamed for carrying out such a large-scale attack so far from their homeland, and follows an incident in Beijing's Tiananmen Square in October which shook the country's Communist leadership.
President Xi Jinping called for "all-out efforts" in the investigation and for the attackers to be punished "in accordance with the law", Xinhua said.
President Xi and Premier Li Keqiang sent condolences to the victims and their families.
Beijing's top security official Meng Jianzhu arrived in Kunming early on Sunday and visited the scene of the attack, which came days before the opening of the annual session of the legislature, the National People's Congress, Xinhua reported.