Almost all afternoon flights from Calcutta were delayed on Friday because of work on the airport’s secondary runway.

Airport officials said around 50 flights of Jet Airways, Kingfisher, Deccan, IndiGo and Air India took off 30-45 minutes later than scheduled.

Work on merging the extended portion of the secondary runway with the main section started around 10am, though delays began to occur only when the taxiway closest to the main runway’s turning pad was blocked.

The main runway will be closed to remove strips of melted tyre rubber from the track once work on the secondary runway is over.