HELSINKI (AP) — Scandinavian Airlines canceled some 50 flights to and from Denmark on Monday after a four-day protest strike by 1,300 cabin crew members in Denmark, but most had returned to work by the evening, the airline said.

Group spokesman Henrik Edstrom said some flights would still be disrupted on Tuesday with full SAS service expected to resume by the following day.

Crews had walked off the job on Friday to protest the airline's plans to transfer employees to a domestic airline acquired by SAS last year, forcing the cancellation of some 150 flights over four days.

Meanwhile in Norway, some flights by Norwegian Air Norway, a subsidiary of budget airline Norwegian Air Shuttle, were disrupted for a third day after 70 pilots started a walkout on Saturday to protest a collective agreement and work conditions. Nine domestic flights in Norway were expected to be canceled Tuesday.

Pilots have warned that they plan to increase the strike to 650 members by Wednesday if no solution is found, Norwegian national news agency said.

Norwegian Air Shuttle stock plummeted, closing down more than 6 percent on the Oslo Stock Exchange.

Officials at Norwegian didn't return calls or answer emails seeking more details.