Health authorities in China claimed that they have found no link between a hepatitis B vaccine and the deaths of 17 children shortly after they were immunized.
An investigation into the deaths, reported between December 13 and 31, has found no evidence that they were caused by the vaccine, the China Food and Drug Administration and the National Health and Family Planning Commission said in a joint statement.
Advertisement"Nine of the cases have so far been confirmed to have nothing to do with the vaccine," said the statement.
But autopsies were still needed to confirm the cause of the other eight deaths, they said.
Reports of the deaths had sparked widespread public concerns after a series of food and health and safety scandals in recent years, largely due to lax and corrupt supervision and law enforcement.
No problems had been detected with the vaccine involved, which was manufactured by domestic producer BioKangtai, the two agencies said.
An epidemiological analysis showed the 17 deaths were due to various "unidentical" problems, including severe pneumonia, kidney failure and suffocation, which were similar to the causes of deaths of children under five monitored by a national reporting network, they said in the statement.
Authorities have halted the use of BioKangtai's hepatitis B vaccines while they investigate the issue.
Previous reports in the Chinese media said more than 44 million doses of the drug were in stock or had been sold to 27 provinces and regions across the country.
Output at BioKangtai and two other Chinese vaccine manufacturers has been suspended since Wednesday because they failed to pass certification standards by a deadline of December 31, Xinhua added.
Vaccination against hepatitis B is one of around 10 free but compulsory inoculations for most children in China. The vaccine is injected within 24 hours of birth, with further doses at one and six months.
Past health and food safety scandals in China have caused intense public anger.
In 2008, six children were killed and thousands of others sickened by tainted baby formula.
Zheng Xiaoyu, former head of China's food and drug safety watchdog, was executed in 2007 for accepting $850,000 in bribes for granting approvals for hundreds of medicines, some of which were later found to be dangerous.
Chinese authorities were accused of covering up the outbreak of Severe Acute Respiratory Syndrome (SARS) in 2003 that killed hundreds of people around the world, but the World Health Organization has more recently praised their openness over bird flu.