China's main inflation indicators remained negative last month, as prices eased amid the slower pace of growth in the economy.

The consumer price index (CPI), the main gauge of inflation, registered a year-on-year decline of 1.4% in May, the National Bureau of Statistics (NBS) said Wednesday morning.

Meanwhile, the producer price index, another measure of inflation at the wholesale level, dropped 7.2% from a year earlier, the NBS added.

This is the fourth consecutive month that the two inflation indicators simultaneously made a year-on-year decline since the CPI and PPI respectively dropped 1.6% and 4.5% in February.

The CPI in April recorded a year-on-year decrease of 1.5%, and the PPI in April fell 6.6% from a year earlier.