The bomb squad was called to conduct its second sweep of Melbourne's CBD on Wednesday afternoon.

Investigators were called to Little Collins Street about 4.10pm for a safety check, not long after clearing Lonsdale Street.

Scenes in Melbourne's CBD where police are investigating reports of a bomb at the corner of Swanston and Little Collins streets. Credit:Julie Kiefel

About 6.30pm, the bomb squad left the scene after finding no safety issues.

Swanston Street had been closed between Collins and Bourke streets, and Little Collins Street was closed between Russell and Elizabeth streets.