Israel declared the northern branch of the Islamic Movement in Israel an unlawful gathering on Tuesday, effectively outlawing the group led by Sheikh Raed Salah.
The decision, made by the Security Cabinet, means that any person or group that officially associates with the organization from now on will be subject to criminal penalties, including arrest. In addition, the organization's property can be confiscated.
Following the decision, police searched more than a dozen of the group's offices around the country, seizing computers, files and funds. Authorities also froze its bank accounts and said that 17 organizations affiliated with the party were served with orders to close down.
Police also called in several of the movement's members for questioning, including Salah, his deputy Sheikh Kamal Khatib, and the organization's head of Jerusalem and Al-Aqsa mosque affairs, Dr. Salman Abu Ahmad.
Police and Shin Bet investigators, who gathered the evidence to back the decision at the government's behest, will now have more leeway in acting against the northern branch of the Islamic Movement. The evidence gathered showed, among other things, the tight ideological connection and public relationship between the northern branch of the Islamic Movement to Hamas and the Muslim Brotherhood.
Security officials made a distinction between the northern and southern branches of the Islamic Movement. While the northern branch is considered radical, the southern branch is considered moderate, and has not been sanctioned.
The movement's connection to Hamas was a major factor in the Cabinet's decision. The two collaborated in joint ventures through the northern branch's institutional activities, and for years, the northern branch's activities have been funded by organizations connected with Hamas.
There were some dissenting opinions in Shin Bet circles regarding the move, raising concerns that the decision might lead to anger and an eruption of violence, and that it could cause the members of the northern branch to move their activities underground, which could make them tougher to track.
The leader of the northern branch of the Islamic Movement, Sheikh Raed Salah, called the decision "unacceptable," and said the Islamic Movement will "keep on its path until its victory, especially on the issue of al-Quds (Jerusalem) and al-Aqsa mosque."
Salah, who is set to start serving an 11-month prison sentence for inciting violence in a 2007 sermon, vowed to take all measures to undo the government's decision.
"The Security Cabinet decision was made following a series of in-depth discussions with all relevant legal and security elements," said Prime Minister Benjamin Netanyahu. "The goal is to stop the dangerous incitement at home and prevent harm to innocent life. My government will continue to act as necessary against incitement and terrorism; at the same time, we will continue to invest resources for the betterment of Israel's Arab and Jewish citizens alike."
Public Security Minister Gilad Erdan said that "The State of Israel must set an example and spearhead the fight against radical Islam, whose messengers we witnessed slaughtering innocent people in Paris, New York, Madrid and Israel.
"The Islamic Movement, Hamas, ISIS, and the other terror organizations have a common ideological platform that leads to terror attacks in the world and the wave of terror attacks in Israel. It is time we use all the tools at our disposal in the fight against terror and those inciting to it," Erdan added.
The Zionist Union party welcomed the decision, and called to outlaw radical right-wing group Lehava (anti-assimilation of Jews and Arabs) and soccer team Beitar Jerusalem's fan group La Familia.
The ban sparked outrage among Arab leaders and lawmakers from the Joint List condemned the move.
Mohammed Barakeh, the head of an umbrella group of Arab Israeli political parties and community leaders, called the decision "an unjustified draconian step." The umbrella organization was set to hold an emergency meeting about the ban.
MK Ahmed Tibi called the Islamic Movement "an authentic part of the High Follow-Up Committee for Arab Citizens of Israel, along with other parties and movement in the Palestinian-Arab society in Israel.
"We view this decision as a criminal act, that targets the entire Arab public and is against our right - and even our duty - to act for our public, including on the issue of al-Aqsa, and attempts by the right wing to change the status quo there," Tibi added.
MK Yousef Jabareen said the decision constitutes as "dangerous political persecution and a serious violation of a national minority's basic right for the freedom of expression, the freedom of religion, and the freedom of assembly.
"This is political and religious oppression, which also causes grave damage to religious, welfare and educational services that the movement provides all Arab residents," Jabareen added.
Hamas, meanwhile, saw the decision to outlaw the northern branch of the Islamic Movement in Israel as a badge of honor, but said the decision was "racist, and hurts Israeli Arabs." The terror organization called on the international community to take responsibility for the decision.
Salah has alleged in speeches and annual rallies under the heading "Al-Aqsa is in Danger" that Israel plans to expand its control there.
Since 2001, the Islamic Movement has bused tens of thousands of supporters to the mosque compound every year to strengthen its Muslim presence.
Several years ago, the movement helped form groups of male and female activists, known as "Morabitoun" - loosely translated as defenders of Islamic lands - who spend hours each weekday at the shrine trying to disrupt visits by Jews.
During periods of tension, police at times block busloads of Islamic Movement supporters from Jerusalem. Earlier this year, Israel outlawed three associations suspected of funding the Morabitoun and later declared the groups illegal.
The Associated Press contributed to this report.