Thousands of passengers have been stranded across Scandinavia as a strike by pilots of Norwegian Air Shuttle continued for a fifth day.

Norwegian CEO Bjoern Kjos says it's "terribly tragic" that 35,000 air travelers were being hit by the strike after several rounds of talks with pilots' representatives failed.

Some 70 pilots walked out Saturday to protest a collective agreement and work conditions at Norwegian Air Norway, a subsidiary of budget airline Norwegian Air Shuttle. The strike expanded Wednesday to 650 pilots.

The cancelations were limited to regional flights between Norway, Denmark and Sweden but some disruptions to flights outside the region were also affected.

Norwegian, Europe's third largest budget airline, flew 24 million passengers last year.