Acts 17:5

‘But the Jews, being moved with jealousy, took to them certain vile fellows of the rabble, and gathering a crowd, set the city on an uproar, and assaulting the house of Jason, they sought to bring them forth to the people.'

Thus ‘the Jews', that is those who were not willing to respond to the new message, (note how here, as in John's Gospel the term is used of those who are antagonistic to the Good News), set about trying to interfere with the ministry of Paul and Silas. In Pisidian Antioch this had been accomplished by utilising the influence of the chief women who were synagogue worshippers (Acts 13:50), but that was not possible here because so many of these chief women were now following Christ (Acts 17:4). So instead they turned to the mob.

The Jewish traders and merchants, or their employees, would know the right people to contact. They turned to ‘vile fellows of the rabble', that is the low life in the marketplace and the docks, people who could always be bribed and depended on to cause an uproar. These then raised a crowd and set the city in an uproar, racing through the streets stirring up trouble and ending up by making a forced entry into the house of Jason, a prominent local Jew who was presumably known to be giving hospitality to Paul and Silas, in order to drag out Paul and Silas and make an example of them (‘the people' being either a popular assembly, it was a ‘free city', or the equivalent of a stirred up lynch mob).

Thessalonica was in fact infamous for being a city in which uproars easily occurred. Cicero tells how when he was sent to see the rulers of Thessalonica on official business the rulers were so unpopular with the masses that he had to sneak into the city at night in order to see them, and then, after some time, he had later to sneak out again and take refuge ‘in the out of the way town of Berea' until the uproars had died down.