Police arrested 31 suspects in Istanbul on Wednesday as part of an investigation into the PKK terrorist organization, according to a security source.
During the province-wide operation, 31 out of 43 suspects who are members of the left-wing Peoples' Democratic Congress (HDK) were arrested for alleged links to the PKK terrorist organization.
A gun, a hunting rifle and a large number of bullets were seized, said the source, who asked not to be named due to restrictions on talking to the media.
The PKK -- listed as a terrorist organization by Turkey, the U.S. and the EU -- resumed its armed campaign against Turkey in July 2015.
Since then, it has been responsible for the deaths of more than 1,200 Turkish security personnel and civilians, including women and children.