AS southwestern Kunming struggles to make sense of the horrific knife attack that left 29 people dead last Saturday, residents in several major cities across China have been unnerved by wild rumours, spread via the Internet and instant chat messages, of a second wave of terror attacks targeting civilians.
The rumours ranged from speculation that five groups of suspected terrorists were on the prowl to unsubstantiated reports of fresh knife attacks in the western city of Chengdu.
The intense online buzz prompted several state media outlets to issue reports dispelling the rampant rumours, such as one involving the arrest of two "terrorists" at an airport in Xiamen, a coastal city in the east.
China's national crime prevention office also took the unusual move of issuing a public appeal for calm on Tuesday, writing on its its official microblog account: "Please don't spread rumours and cause unnecessary panic."
The agency also published a list of 15 rumours that reportedly went viral after the massacre in Kunming on Saturday, and urged the public not to be taken in by such hoaxes.
The agency's plea for calm came on the same day that a pungent smell on a train in Guangzhou sent frightened passengers fleeing a station, with luggage scattered around and at least four people injured in the stampede, according Chinese media.
"I was sitting at the rear of the train and saw the people rushing to the front, with many tripping and falling," Mr Liang Ziqi, a college student, posted on his microblog on Tuesday. "It shows that many people are still living under the shadow of the Kunming event on March 1."
The incident came hard on the heels of rumours that some attackers have made their way into the southern city, which houses a population of more than 10 million.
About an hour after the incident, Guangzhou's police department said the smell came from a pepper spray that two teenagers were fiddling on the train. The event was under further investigation, police added.
Guangzhou is one a host of cities that saw security tightened after the Kunming violence suspected to have been carried out by Muslim Uighurs from restive Xinjiang province.
Beijing, where the country's annual parliament session kicks off on Wednesday, had armed policemen patrolling Tiananmen Square, airports and train stations.
"I've never seen the city's security as strict as this," a cab driver told the Information Times on Monday, adding that armed police stood guard at almost every junction.
In Chengdu, students in Sichuan Conservatory of Music were gripped by fears on Monday, after rumours that police had arrested two of the three knife-wielding Uighurs at the school's gate.
But police were quick to clarify that "no such case has been reported" and identified a student in the music school as the rumour creator, but gave no details about the motive.
Mr Huang Chuxin, the city's Communist Party chief, has vowed "zero tolerance" for "violent and terrorist activities", ordering a 24-hour patrol at key commercial districts, reported the Chengdu Daily on Tuesday.
Fears of attacks began to sweep the nation following the slaughter in Kunming, where eight assailants stabbed people at random, leaving 29 dead and more than 130 wounded.
Four suspects were gunned down at the scene, with the remaining arrested, officials said, adding that it was a act of terror organised by Uighur separatists.
The People's Daily, the mouthpiece of the Communist Party, led the media to dismiss rumours on Tuesday, while lauding some Uighurs' good Samaritans, including a 17-year-old who rescued a Han woman in 2012.
On its Weibo account, the newspaper posted: "Black sheep exist in almost every place and every nation, but most of the people are just ordinary good Samaritans,"