Established by Colonel Alparslan Türkeş in the late 1960s, it rose to prominence during the late 1970s political violence in Turkey when its members engaged in urban guerrilla warfare with left-wing activists and militants. Scholars have described it as a death squad, responsible for most of the violence and killings in this period. Their most notorious attack, which killed over 100 Alevis, took place in Maraş in December 1978. They are also alleged to have been behind the Taksim Square massacre on May Day, 1977. The masterminds behind the Pope John Paul II assassination attempt in 1981 by Grey Wolves member Mehmet Ali Ağca were not identified and the organization's role remains unclear. Due to these attacks, the Grey Wolves have been described by some scholars, journalists, and governments as a terrorist organization. The organization has long been a prominent suspect in investigations into the Turkish "deep state", and is suspected of having had close dealings in the past with the Counter-Guerrilla, the Turkish branch of the NATO Operation Gladio, as well as the Turkish mafia. Among the Grey Wolves' prime targets are non-Turkish ethnic minorities such as Greeks and Armenians.