India's capital region of Delhi on Sunday announced an extension of its coronavirus lockdown until May 17, with tightened restrictions such as suspension of Metro trains.

The lockdown, first imposed on April 20 and previously extended twice, had been scheduled to end at 5 a.m. on Monday.

A shopping area is deserted in New Delhi on April 17, 2021, amid a weekend curfew due to the coronavirus pandemic. (Kyodo) ==Kyodo

India is suffering the world's fastest pace of coronavirus infections, with the number of confirmed cases per day exceeding 400,000 over the last four days and the cumulative number of infected people reaching about 22.3 million.

On Sunday, the death toll exceeded 4,000 for the second consecutive day, bringing the total to about 242,000.

Delhi's Chief Minister Arvind Kejriwal said that while the positivity rate in the city has been reduced from 35 percent on April 26 to around 23 percent now, the number of infected people is still high. He said any slackness now would squander the gains achieved so far in battling the current wave of the pandemic.

The chief minister said that oxygen supply in Delhi had improved significantly in the last few days, to the extent that he has stopped hearing things like "there's just 30 minutes of oxygen left!" for hospitalized COVID-19 patients.

However, he revealed there is still a vaccine shortage and said he was seeking help from the central government.

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