Under surveillance

My friends and myself socially got together for a drink and noticed a group of ethnic Eritrean having a drink in the same pub as we were everything was peaceful and no trouble but it was a busy night all of a sudden police vans came and surrounded the pub and a C.I.D. car with two officers who came out and entered the pub the police took out two of the ethnic out of the pub handcuffed and other police escorted a female ethnic out of the pub and she was searched and let go another white man was getting handcuffed by the C.I.D officer and resisted so the officer warned him and reached for his taser however the suspect initially gave in and was handcuffed the police then took the ethnic suspects into the police van but released white suspect and took his statement. I asked the pub manager did he call the police he said no the police were following the ethnic group and then raided the pub to arrest them.