The latest and strongest of the quakes was the 4.2 Richter quake that shook the city at 12:18 p.m. on Thursday.
Ganas said Patras residents were alarmed by this latest tremor but it did not cause any damage, adding that the pattern of quakes was being studied by seismologists.
The epicentre of the cluster of quakes that began last Sunday is west of the Rio-Antirrio bridge and most of the earthquakes have been superficial, with a depth ranging from four to 17 kilometres. Because of this shallow depth, this means they are more strongly felt in the surrounding settlements of Patras, Rio, Nafpaktos and other regions of Achaia and Aitoloakarnania.
According to local residents, the frequent earthquakes began last Friday.