BANGKOK, May 1 (Reuters) - Thailand on Saturday (May 1) reported a new daily record of 21 coronavirus deaths, the health ministry said.

The ministry reported 1,891 new cases in a fierce third wave of infections after a year of relative success in controlling the virus.

Thailand's total number of infections is 67,044 since the pandemic began last year, with a total of 224 deaths.

Thailand has yet to start its mass vaccination drive but has been administering the 2.5 million doses of the Sinovac vaccine it has received so far mainly to health workers or people deemed at risk of exposure.

The mass vaccinations will rely heavily on 61 million shots of AstraZeneca's vaccine to be produced locally from June.

Thailand will also receive another 3.5 million doses of the Sinovac vaccine next month, a senior health official said on Friday.

One million doses will arrive on May 6 and 2 million more are due by the end of May, said Witoon Danwiboon, head of the Government Pharmaceutical Organization (GPO).

An additional 500,000 doses would be donated by the Chinese government, he told a briefing.