British trip hop group Massive Attack are known for their ?outspoken political stances. (EPA PHOTO)British trip hop group Massive Attack are known for their ?outspoken political stances. (EPA PHOTO) Credit: AAPThe British band Massive Attack says its members were detained by Singapore police and "isolated and separately questioned" after the two performers raised a Palestinian flag at their concert in the city-state. Police said last Friday the band's actions "could potentially harm the racial and religious harmony in Singapore" and that two band members were issued with stern warnings and barred from re-entering Singapore. Massive Attack, formed in Bristol in the west of England in 1988, are known for their outspoken political stances, with videos during their concert highlighting conflicts in Iran, Sudan, Gaza and Ukraine.