Greater Manchester Police (GMP) said a search was ongoing at premises in Pilsworth in a statement released this afternoon.
Helicopter footage showed around a dozen forensic officers at the scene, where a large red tent has been erected.
Cowardly suicide bomber Salman Abedi killed 22 people at an Ariana Grande concert at Manchester Arena last Monday.
A GMP spokesman said: "Officers investigating the attack on the Manchester Arena are searching a site in Pilsworth, Bury.
"The search is currently ongoing."
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Around a dozen forensic officers are at the scene in Pilsworth
Police have been working round-the-clock since Abedi's horrific attack, the worst terrorist atrocity in the UK since the 2005 London bombings.
A total of 16 arrests have been made in connection with the attack, although two people have since been released.
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It has been reported that MI5 has launched two urgent inquiries into whether it missed the danger posed by Abedi.
Salman Abedi killed 22 people in the terror attack last Monday
A senior Whitehall source previously has said Abedi was a "former subject of interest" to the security services whose risk "remained subject to review".
But Home Secretary Amber Rudd said on Sunday she would "not rush to conclusions" that agents "somehow missed something".
In the wake of the attack it emerged British counter-terror authorities were grappling with 500 investigations into 3,000 individuals.