Officers said the encampment group gathered in Glade Lane moved onto nearby land behind McNair Road, Norwood Green , Southall, on Wednesday (September 13) evening.
Ealing Council confirmed a group had camped up at Havelock Estate.
Norwood Green Police are working with Catalyst Housing and Ealing Council to resolve the situation.
The force tweeted: "The encampment in glade lane has moved onto land behind McNair road Catalyst Housing are aware."
Another group of travellers were reported to be in Glade Lane earlier on Wednesday September 13.
According to police, at the start of the week a group were spotted camped up at Merick Road in Southall, at the old Esso site.
An Ealing Council spokesman said: “As soon as we were aware that travellers had set up camp at Havelock Estate, officers from the council liaised with and are supporting the landowner.
"We are now taking the next steps to resolve this situation."
A Catalyst Housing spokesman said: “We are fully aware of the illegal encampment on our property and we have instructed our legal consultants to begin the eviction process.”
Local policing team, Northfields SNT, shared the video footage below on Twitter just after 2pm on Thursday August 10.
Posting to Twitter, the force said: "Travellers all leaving #EalingCommon currently following eviction & partnership work with @EalingCouncil."
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