BEIJING - A year after the massive Sichuan earthquake leveled hundreds of schools, sparking allegations of corruption and shoddy construction, China finally gave Thursday its first official tally of the numbers of students dead or missing: 5,335.

The government began its count hours after the magnitude-7.9 temblor razed huge portions of the southwestern province on May 12, 2008, but has refused until now to say how many students were among the nearly 90,000 people killed or missing. Another 5 million people were made homeless.

Thousands of classrooms collapsed while buildings around them remained intact. It has become a politically charged issue and an enduring source of bitterness for parents trying to find answers and closure.

Parents say the schools crumbled so easily because corruption and mismanagement led to slipshod construction and weak buildings that were not up to code. Some say materials meant for school construction projects were sold on the side by contractors for personal gain.

So far no one has been held responsible or punished.

Officials, however, blame the sheer power of the temblor as the main cause for the number of flattened schools and have said compiling and confirming the names of the students was a complicated process.

Tu Wentao, head of Sichuan's education department, announced the student death toll at a news conference in the provincial capital of Chengdu.

No reason was given for the release of the figures on Thursday -- just days before the one-year anniversary of the disaster -- but some say it could be a sign that the government is attempting to stem the ongoing discontent over the issue.

Yet grieving parents took little solace and were skeptical of the toll.

"Announcing the numbers won't bring us any consolation," said Liu Xiaobin, whose 11-year-old son was killed when the three-story Fuxin No. 2 Primary School sank into the ground and the rest of the neighborhood remained standing. "We want the government to investigate the situation."

Liu and other parents have petitioned and protested, only to be detained or warned against speaking out. Activists sympathetic to their cause have been harassed or taken away by police.

In a transcript of the press conference posted on the Sichuan government's Web site, the officials said that "once there is concrete evidence to prove that problems exist in building designs and construction, relevant departments will investigate according to law."

Ai Weiwei, an avant-garde artist and high-profile critic of Beijing's policies, said Thursday's announcement appeared to show that the "pressure of the common people, pressure from the media" had made some difference.

But he said it was still an empty gesture.

"It didn't give any names or any other information on where they died, which schools or which classes they were in," Ai said in a telephone interview. "This is nonsense."

In his blog, Ai has confirmed almost 5,000 student names and estimates that the toll could reach 8,000. At least 20 of his helpers have been detained by local authorities, he said.

Tan Zuoren, another activist who conducted his own investigation into 64 schools in the quake zone, estimated that more than 5,600 students died or were missing. Tan, who has since been detained on suspicion of subversion, said that number was incomplete.

Liu Xiaoying, whose 12-year-old daughter was also killed in the Fuxin No. 2 Primary School, said she is sure that the number of dead schoolchildren is much higher.

"I hope the investigation will continue and that the people responsible will be seriously punished," said Liu, who is under tight surveillance after traveling to Beijing twice to petition the central government.

"I hope the government will really do what they say they would and not brush off us parents," she said. "If this is the case, the hearts of my husband and I will be more at ease."

Also Thursday, the official China Daily newspaper reported that a circular issued by the Cabinet was ordering that safety controls over the construction and rebuilding of schools be strengthened.

The circular said there would be severe punishment for those who engage in illegal practices.