The Black Panthers (named for the animal and not the Black Nationalist group) are a terrorist and vigilante group loosely affiliated with al-Fatah in the Palestinian territories. The group is most known for executing Palestinian collaborators during the first Intifada (1987-1991) and several high-profile kidnappings in Gaza in 2005.
The Panthers were apparently formed in 1989, shortly after the beginning of the first Intifada. Although affiliated with and funded by al-Fatah, the group's heavy-handed tactics and brutal violence provoked public rebukes from "mainstream" al-Fatah leadership. In addition, the Panthers firmly rejected any peace overtures to the Israelis. They joined other allied groups such as the Fatah Hawks and Hamas in completely rejecting the 1993 Oslo Accords. As such, the group can be considered a militant nationalist-separatist group, dedicated to the destruction of Israel and the establishment of a secular Palestinian state.
The group was vicious in its dealings with collaborators and was said to have killed close to 100 Palestinians from 1989-1993. Along with collaborators, the group also killed to settle family disputes, business rivalries, and for extortion purposes. The Panthers also targeted Israeli military personnel in the West Bank (the group was originally based in Jenin), thus provoking a large-scale response. Israeli undercover units hunted the Panthers throughout the first Intifada up until after the signing of the Oslo Accords. Several leaders of the group were either killed or arrested, and the Panthers' operational capability was whittled down considerably.
With the signing of the Oslo Accords and the Israeli crackdown, the Black Panthers ceased to be the feared group they once were. However, in the period after Oslo, the group maintained arms and continued low-level violence. In 1996, after a Hamas suicide bombing which killed 20 Israelis, the Black Panthers were banned by Yasser Arafat, along with several other groups. From that point on the group maintained an extremely low profile.
The Black Panthers re-emerged in 2005 with two high-profile kidnappings of international journalists in the Gaza Strip. The group made demands for jobs and later released the hostages unharmed. The location of the abductions (not in the West Bank), the tactics employed by the group, and the somewhat timid demands suggest that the Black Panthers in Gaza were simply supporters and admirers of their vicious forefathers, the West Bank Black Panthers. Kidnappings of foreigners have become increasingly common in the Gaza Strip since Israeli disengagement, and numerous small groups have claimed these attacks.
The Black Panthers in their original form do not appear to be an active terrorist entity. Although a group exists using their moniker, the threat from the current iteration of the Black Panthers appears to be relatively low. However, the group is active and could be responsible for terrorist violence in the future.