Town youngster Idris El Mizouni said he was "appalled" when home fans at his loan club Cambridge United booed players taking the knee.
Tunisian international El Mizouni, 20, said he was embarrassed by the decision of a number of fans who booed the act at kick-off against Colchester, which aims to stand against racism and discrimination of all forms.
In a tweet, also posted word-for-word by other Cambridge players, the midfielder said: "Appalled and embarrassed by the section of fans who booed us players taking the knee tonight, itβs 2020 and the action is a symbol of solidarity!
"I want to thank the fans who overhauled the boos with applause but this cannot continue."
Cambridge head coach Mark Bonner said the club will continue to support the movement for equality, adding: "It's embarrassing, unacceptable and we don't stand for that."
The boos come after a similar incident happened at opponents Colchester earlier this month, which led to club chairman Robbie Cowling saying fans who boo the gesture are not welcome at his club.
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