North Korea's new suspected COVID-19 cases remained below 600 for the second consecutive day, according to its state media Friday.

More than 500 people showed symptoms of fever over a 24-hour period until 6 p.m. the previous day, the official Korean Central News Agency (KCNA) said, citing data from the state emergency epidemic prevention headquarters.

It did not provide information on whether additional deaths have been reported. As of July 5, the death toll had stood at 74, with the fatality rate at 0.002 percent.

The total number of fever cases since late April came to over 4.77 million as of 6 p.m. Thursday, of which over 4.76 million had recovered and at least 1,120 others are being treated, it added.

The North's daily fever tally has been on a downward trend after peaking at over 392,920 on May 15.

The KCNA reported that the North is strengthening its anti-epidemic measures by devising a nationwide medical checkup system.

"In order to detect cases of various kinds of infectious diseases in their early stages, establish quarantine and treatment measures and stop the spread of the epidemic, the state emergency epidemic prevention headquarters organized a nationwide intensive medical checkup," it said.

It added that polymerase chain reaction tests are being conducted every day on water collected from major rivers and reservoirs in border areas, dust from "epidemic danger zones," and seafood from coastal areas.

Earlier this month, the North claimed its coronavirus outbreak originated from "alien things" found near the inter-Korean border, alluding to balloon-carried materials sent at times by North Korean defector groups in South Korea, such as anti-Pyongyang leaflets.

Pyongyang disclosed its first COVID-19 case on May 12 after claiming to be coronavirus-free for over two years and implemented nationwide lockdowns. (Yonhap)