FRANKFURT (Reuters) - Trade union workers are going to strike at Germany’s biggest airport in Frankfurt on April 27, trade union Verdi said in a statement on Friday.

Strikes will also affect airports in Munich, Duesseldorf, Cologne/Bonn, Dortmund and partially Hanover, it said.

At Frankfurt, ground crews, check-in staff, repair workers and the fire department will be on strike until about 1300 GMT, the statement said.

Verdi union demands a 6 percent wage increase for its roughly 2.1 million workers and said that travellers should prepare for massive disruptions in air flight travel.

(The story was refiled to say 1300 GMT, not 1400 GMT)