The writer continues giving background information about Stephen and other people that is important to understanding the story. (See: [[rc://en/ta/man/jit/writing-background]])
The word "arose" is an idiom that represents beginning to act. These people did not begin to rise into the air, nor did they necessarily get up from a sitting position. Alternate translation: "some people ... Asia, began to debate against Stephen" (See: [[rc://en/ta/man/jit/figs-idiom]])
Possible meanings are 1) the Cyrenians, the Alexandrians and those from Cilicia and Asia were all members of the synagogue of the Freedmen; 2) the Cyrenians and the Alexandrians were members of the synagogue of the Freedmen, but those from Cilicia and Asia were not; or 3) there were three separate groups of people: those from the synagogue, those from Cyrene and Alexandria, and those from Cilicia and Asia.
"Freedmen" were probably ex-slaves from these different locations. It is unclear if the other people listed were part of the synagogue or just participated in the debate with Stephen.