CANBERRA, June 3 (Reuters) - Australian health authorities raised the H1N1 flu alert in hardest-hit Victoria state on Wednesday as confirmed cases jumped to 502 nationwide.

The alert in Victoria, which has the bulk of Australian cases, was raised to "sustain", meaning containment was not possible and people thought to have been exposed would no longer be quarantined, national Health Minister Nicola Roxon said.

Roxon said the new alert level for Victoria, which has 395 confirmed H1N1 cases, was in a modified form, meaning sporting events could still proceed.

"We have no advice that these events should be stopped," she told reporters in Canberra.