The travellers appeared on Thursday morning (October 12) outside the B&M discount store in Willow Tree Lane Retail Park in Glencoe Road.
A spokesman for B&M stores confirmed that a number of caravans had appeared on the property, and they had alerted authorities to the incident.
Metropolitan Police has been approached for further clarification but has not yet responded.
The store is continuing to trade as normal and apologised to customers for any inconvenience caused.
A B&M spokeswoman, said: “There are currently a number of caravans parked on the Yeading store’s car park – we’ve been in contact with the authorities who are currently handling the situation.
"The store is trading as normal and we apologise to our customers for any inconvenience caused.”
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