The Swiss central bank said on Thursday it would continue to enforce its cap on the franc's exchange rate against the euro, pledging to buy "unlimited" foreign currency if necessary.

Read the full article: Swiss central bank stands by currency cap

Sounds like SNB is getting worried

Hardly they are just making sure the traders of the world know there is no point in trying to artifically make a windfall.

By making a strong statement they will have to spend less since you are less likely to bother if you are aware that the SNB is going to override any gain

Whereas according to the newspapers "The Swiss franc was the strongest major currency today, rising against both the euro and the dollar"