IDF troops continued to arrest Palestinian suspects in the West Bank on Saturday, the ninth day of an operation to search for three kidnapped Israeli teenagers who were abducted June 12 from a hitchhiking post in the Etzion Bloc of settlements in the West Bank.

The security forces also called in fire trucks and other emergency vehicles, as their searches focused on dozens of caves, wells, water cisterns, and other sites where the kidnappers and their captives might be located.

Israeli officials said at least 10 people were detained overnight, as forces raided 15 Palestinian charity organization with alleged ties to Hamas. The IDF said it searched over 140 homes overnight.

“Ten people were arrested overnight, bringing to 330 the number of wanted Palestinians arrested since the beginning of the operation,” a spokeswoman for the army said.

Palestinian officials said a 60-year-old man died of a heart attack while trying to prevent Israeli troops from searching his house, Israel Radio reported. Palestinian sources said around 30 people were arrested overnight, and that 10 people were injured during a confrontation between Israeli troops and Palestinian rock throwers in Ramallah. Some of the wounded were hit by rubber bullets, others by tear gas, Palestinians said.

An area north of Hebron which was declared a closed military zone on Friday remained cordoned off on Saturday, with soldiers searching house-to-house in the area and no outside traffic allowed in.

A senior Israeli government official said Friday that the noose was tightening around the kidnappers.

Speaking to Channel 10, the official said that, based on security assessments, the teens were still somewhere in the West Bank and their abductors were unsuccessful in moving them in the direction of Jordan, Gaza, or Sinai.

Naftali Frankel, Gil-ad Shaar and Eyal Yifrach were last seen late on the night of Thursday June 12. Several Palestinian groups have taken responsibility for their abduction but the authenticity of the claims is questionable.

The Israeli government has pointed the finger at Hamas and said it holds the Palestinian Authority responsible for their fate. PA President Mahmoud Abbas on Wednesday criticized the kidnapping, said the youths must be returned, and confirmed ongoing security cooperation with Israel to try to locate them. Hamas has praised the kidnapping without claiming responsibility, and slammed Abbas for siding with Israel.

Prime Minister Benjamin Netanyahu met with the families of the three Friday and updated them on the progress of the search. Frankel’s uncle was later quoted saying that all indications were that the three are alive. On Thursday Netanyahu said Israel knew more about their fate than it had done a few days earlier, and Defense Minister Moshe Ya’alon said the operation to find the three was making progress. Also Thursday, an Israeli official named a deported Hamas terror chief, Saleh al-Arouri, as a suspect in orchestrating the kidnapping.

Israeli forces are embarked on a massive campaign to locate the three kidnapped boys while simultaneously destroying parts of the Hamas terror infrastructure in the West Bank.

Over the past week, thousands of Israeli troops have searched hundreds of locations in the West Bank and arrested more than 300 Palestinians, many of them from Hamas, including some who were freed in a 2011 prisoner exchange for Hamas-kidnapped Israeli soldier Gilad Shalit.

Israeli officials have said that their working assumption is that the boys are alive.

AFP contributed to this report.