Witnesses say they saw four police vans and a number of officers arrive on the Pilsworth Road landfill site earlier today.
Police have closed off access to the site, with one vehicle standing guard at the entrance.
Officers are also positioned at entry points to a public pathway which surrounds the site to prevent access to the tip.
Greater Manchester Police has confirmed the site is being searched as part of the investigation into the atrocity for the blue suitcase that was seen by the bomber Salman Abedi.
The public are being asked to contact the police immediately if they see the piece of luggage, which officers have no reason to believe contains anything dangerous but are asking people to be cautious.
— G M Police (@gmpolice) May 29, 2017