Officers from Home Office Immigration Enforcement raided the Asian Fusion restaurant in Littlewick Green this afternoon.
Maidenhead resident Victoria Spracklen was in the Bath Road restaurant with work colleagues at about 12.15pm when the officers burst in.
She said: "There were about seven or eight, they poured in through the front and side doors. They pulled all the staff out of the kitchen and put them in a corner.
"It was just like you see on the television. They were demanding passports, ID, asking why they were here.
"There were six customers in there and we just carried on eating. About 10 staff were being questioned but there were three left to carry on serving us."
A spokesman for the Home Office Immigration Enforcement confirmed this afternoon that four Bangladeshi men had been arrested after the latest raid.
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