A 28-year-old man has been arrested by police in California over the stabbing of a US airman hailed as a hero for helping to thwart a European terror attack.

A US airman hailed a hero for helping to stop a terror attack on a French train has been stabbed and seriously wounded outside a bar in his home town, in what police said was an alcohol-related brawl.

One of the Americans who overpowered a gunman on a Paris-bound train this summer has been stabbed repeatedly in California.