NEW DELHI (Reuters) - India's daily COVID-19 infections rose by 50,040 on Sunday, official data showed, as concerns grew about the detection of the highly infectious Delta variant of the coronavirus in some states.

       The COVID-19 death toll in the country rose by 1,258, including 511 deaths reported from the state of Maharashtra, the health ministry data showed.

       New variants are a particular concern in India, where more than half the population has not been vaccinated. Less than 6% of India's adult population of 950 million has received two doses.

       At least 20 cases have been found linked to the Delta variant, which India last week designated a variant of concern last week, according to the health ministry.

       India's official death count is now 395,751, but experts and global health agencies such as the World Health Organisation believe the toll may be much higher. Of the 35.51 million people infected, 29.25 million have recovered.

       State governments eased lockdown restrictions earlier this month after a fall in cases, but scientists fear that the presence of the Delta variant, which was first detected in India, and the slow pace of vaccination could trigger another wave of infections.

       (Reporting by Manoj Kumar; Editing by William Mallard)