The Australian Federal Police have raided the offices of Labor staff in Melbourne over the alleged leak of documents from the NBN.

Opposition Leader Bill Shorten confirmed the AFP raids on Thursday night, saying they were being carried out in relation to the leaking of confidential documents discussing the National Broadband Network.

“It relates to his (Prime Minister Malcolm Turnbull) embarrassment over the fact there was a massive blowout of costs of billions and billions of dollars and, of course, huge delays to the delivery and the rollout of the NBN,” Mr Shorten told reporters in western Sydney.

One of the parliamentary offices raided by the AFP included that of Labor Senator Stephen Conroy. It is understood another Melbourne office was raided in connection with a staffer of Labor’s communications spokesman, Jason Clare.

In February, Fairfax Media – quoting an internal NBN progress report – claimed the $46 billion network had fallen two-thirds short of its benchmark construction timetable.

– with other agencies