Washington - A man suffering heart problems died from were called complications from the H1N1 flu strain, the third human fatality reported in the US so far, according to the Seattle Times newspaper.

The online edition reported that preliminary test results on Saturday showed the man, aged in his 30s, had contracted the new influenza and died of pneumonia.

The national Centres for Disease Control (CDC) had not yet confirmed the flu as the cause of death.

The two previously reported human deaths in the nation occurred in the state of Texas, which borders Mexico, the worst-affected country.

The total number of confirmed H1N1 flu cases increased by 615 to 2,254 patients by midday Saturday, according to the CDC.

The cases were spread out over 43 states and the federal District of Columbia.