MUNICH (dpa-AFX) - The trade union Verdi has called on aviation security staff to go on warning strikes at several German airports on Friday. Munich Airport announced that the union's call for strikes from Thursday to Friday morning at 6.00 a.m. would only affect the checkpoints for staff in Munich, but that this could lead to restrictions in flight operations. Passengers should check the current flight status with their airline before traveling. "The security checkpoints for passengers are not affected by this strike and are open as normal," the airport company announced./rol/DP/stw