Students of a Japanese school in the southern Chinese city of Shenzhen and their parents were still haunted by the fatal stabbing of a schoolboy as Friday marked one month since the incident, with Beijing yet to reveal the suspect's motive or other information.

The killing of the 10-year-old pupil, whose father is Japanese and mother is Chinese, has left a deep psychological scar on students at the school, which reopened earlier this week with many opting to attend classes online amid ongoing safety concerns.

The victim was stabbed on his way to the school and the 44-year-old suspect was apprehended at the scene. Despite Japan's repeated requests to clarify the facts, China has not provided sufficient information including whether the attacker targeted Japanese nationals in particular, insisting it was "an isolated incident."

The Japanese government has sent counselors to the Shenzhen school to provide psychological care. But in one class, some 80 percent of students chose to study online even after the reopening of the educational facility.

Some parents have said they cannot sleep well due to anxiety, while other families have decided to return to Japan. "I want children to return to their daily life but if any trouble happens, damage would be irreparable," a father said.

At present, several dozen Shenzhen police officers keep watch near the school when students commute to and from the facility. Before the attack, more than half of the school's students commuted on foot, but now they are required in principle to ride a bus or taxi in an effort to reduce risks.

Students now face a tense atmosphere, with curtains drawn over the windows of some school buses during the commute. The stabbing occurred on the 93rd anniversary of a Japanese bombing of a railroad track near Shenyang, the start of the Manchurian Incident that led to Japan's invasion and occupation of northeastern China.

The incident came less than three months after a knife attack at a bus stop in Suzhou near Shanghai in June, in which a Japanese mother and child were injured. A Chinese woman who worked as a Japanese school bus attendant died while attempting to stop the assailant.

On Thursday, Keiichi Iwamoto, director general of the Japanese Foreign Ministry's Consular Affairs Bureau, met with Chinese Vice Foreign Minister Deng Li and other senior officials in Beijing and made a fresh demand for China to share information with Japan on the cases in Shenzhen and Suzhou "as soon as possible."

His visit followed a meeting between Japanese Prime Minister Shigeru Ishiba and Chinese Premier Li Qiang in Laos last week, during which the new leader strongly urged Beijing to take immediate measures to ensure the safety of Japanese expats and tighten control over hateful social media posts in China targeting Japanese citizens.

Iwamoto told reporters that the Chinese officials said they were "fully aware of" groundless social media posts and showed readiness to deal with them if they were deemed to violate the country's laws. Some Chinese social media posts claim that Japanese schools in China train spies.

The Chinese officials also suggested Beijing will provide an explanation for the Shenzhen stabbing case based on progress in judicial procedures, Iwamoto said, adding they indicated court hearings on both the Suzhou and Shenzhen incidents will be open.

However, some Japanese residents in China were skeptical about Beijing's intention to clarify the facts behind the deadly stabbing. "They can be swept under the rug," a Japanese national in Shenzhen said.

The Japanese business community has also been alarmed by the situation. The Japanese Association for the Promotion of International Trade has urged Beijing to "recognize the graveness" of the stabbing incident.

"Unless China shows resolve to take concrete measures, some Japanese companies could withdraw" from the Chinese market, a source familiar with Sino-Japanese relations said of the situation as abusive social media posts continue unchecked.