Nine Palestinians, including an elderly woman, were killed and several were wounded when Israeli troops stormed the Jenin refugee camp in northern West Bank on January 26.

The Israeli Defense Forces (IDF) said in a statement that its troops launched an operation in Jenin to foil “imminent attack plans” by the local wing of the Palestinian Islamic Jihad (PIJ). According to the military, three members of a PIJ cell were killed and a fourth was arrested. No Israeli soldiers were hurt in the clashes, the IDF said.

“During an attempt to arrest them, the wanted men opened fire and were killed in an exchange of fire with our forces,” the IDF said. “The wanted men, PIJ operatives, have been involved in recent extensive terror activity, and are suspected of carrying out several shooting attacks against IDF forces, and planning other significant attacks.”

The military said that the raid against the PIJ cell’s hideout in the camp was launched following “accurate intelligence” provided by the Shin Bet security agency.

An IDF officer told reporters that troops used shoulder-launched rockets and other explosives against the hideout, in a tactic known as “pressure cooker,” to force PIJ fighters out.

From its side, the PIJ said its fighters in Jenin opened fire on the Israeli troops and detonated explosive devices during the clashes. As a result, several vehicles of the IDF were damaged and had to be towed out form the camp. A small Israeli drone was also downed.

The Palestinian Authority Health Ministry said in a statement that nine Palestinians were killed, with 20 more wounded, including four listed in critical condition. The fatalities included a woman, identified as 60-year-old Magda Obaid. The IDF was probing her death, an Israeli military source said.

The IDF attack on Jenin was condemned by Palestinian President Mahmoud Abbas, who announced three days of mourning over the deaths of the nine Palestinians.

Israeli Prime Minister Benjamin Netanyahu is set to hold an assessment later in the day on the operation. The IDF is reportedly preparing for an escalation in other areas as well, including the Gaza Strip and the Temple Mount in Jerusalem’s Old City.

Tensions has been on the raise in the West Bank since last year. This month, at least 29 Palestinians were killed in Israeli operations within the occupied region. Jenin was the main focus of many of these operations.