As the search for three missing Israeli teenagers entered its second day on Saturday morning, Palestinians reported that Israeli security forces had conducted a series of arrests in the Hebron region overnight.

Hamas said 16 of its members had been arrested, including several former prisoners. It was unclear what connection, if any, these men had to the youths’ disappearance.

IDF Chief of Staff Lt.-Gen. Benny Gantz was meeting with top IDF commanders in the West Bank Saturday morning to get a situation report.

The West Bank yeshiva students were reportedly last spotted at a hitchhiking post in the vicinity of Hebron on Thursday night. No one has seen or heard from them since.

Israeli security forces conducted a massive manhunt overnight Friday, as part of an ongoing investigation into the disappearances. One report indicated that the military was using surveillance balloons as part of the search.

Palestinian Authority security forces were coordinating and cooperating with Israeli officials in the efforts to find the three, Channel 2 reported.

Various local reports indicated overnight that Israeli military officials increasingly believe that a torched car found by Palestinian police near Hebron early Friday was used in the presumed kidnapping.

The vehicle, a Hyundai i35, was a relatively new car, which authorities fear was used by the suspected kidnappers.

The Shin Bet security agency is also investigating the possible use of a tunnel by the alleged perpetrators to hide the missing boys, reported Ynet News.

At around midnight on Friday, hundreds of people gathered at the Wailing Wall in Jerusalem’s Old City to pray for the well-being of the three Israeli teens, one of whom also holds US citizenship.

Meanwhile, Palestinian Authority President Mahmoud Abbas made no comment about the yeshiva students while speaking at a meeting of his Fatah party Friday. But Hamas officials, in several messages, rejoiced over the kidnappings while not taking responsibility.

Hamas spokesman in Gaza Husam Badran said “the Hebron operation is a great success for the [Palestinian] resistance in the West Bank.”

Earlier Friday, Prime Minister Benjamin Netanyahu told US Secretary of State John Kerry over the phone that since the announcement of a unity government between the Fatah-led PLO and Hamas in April, “the situation on the ground has been destructive.”

Palestinian Authority President Mahmoud Abbas (photo credit: Issam Rimawi/Flash90)

Palestinian Authority President Mahmoud Abbas (photo credit: Issam Rimawi/Flash90)

“This is the result of letting a murderous terrorist organization enter the Palestinian government,” the PM said.

Netanyahu said he holds Abbas responsible for their well-being.

A Palestinian official cited by AFP said that Netanyahu had telephoned Abbas, but provided no further details. There was no confirmation of the call by Israel.

Kerry also spoke Friday with Abbas regarding the suspected abduction. According to Israel Radio, the secretary of state expressed his concern for the welfare of the three youths and said he hoped they would soon be reunited with their families.

“We are working with the government of Israel and with the Palestinian Authority to try to ensure the situation is resolved quickly and that the three teenagers are safely reunited with their families,” State Department spokeswoman Marie Harf said Friday

General Adnan al-Damiri, spokesman for the Palestinian Authority’s security services, described Netanyahu’s remarks, holding Abbas accountable, as “mad.”

He said the PA had no authority in the Gush Etzion area, a settlement bloc under total Israeli civilian and military control.

“Even if there was an earthquake, Netanyahu would blame the Palestinian Authority,” he told AFP.

Another Palestinian official said the PA security services were “cooperating” with Israel to gather information on the teenagers’ disappearance.

At a meeting in London Friday, Justice Minister Tzipi Livni urged Kerry to help secure the safe release of the three yeshiva students by working alongside Abbas to locate the teenagers.

Israel’s security forces were continuing their large-scale operation Friday to locate the three teenagers, and roadblocks were set up around the West Bank to prevent the possible transfer of the three to the Gaza Strip.

The searches were focused around the Palestinian village of Dura and the South Hebron Hills, according to reports.

A senior defense official said that Israel was operating on the working assumption that the feared kidnappings were a hostage situation.

The official told Channel 2 that authorities were waiting for better intelligence surrounding the events or for a Palestinian group to take responsibility. A Salafist jihadi organization called Dawlat al Islam issued a claim of responsibility for the incident, but it was not clear whether the claim had any credibility.

Prime Minister Benjamin Netanyahu and Defense Minister Moshe (Bogie) Ya'alon meet on June 13, 2014, as security forces search for three missing yeshiva students, feared kidnapped in the West Bank.  (photo credit: Haim Zach/GPO/Flash90)

Prime Minister Benjamin Netanyahu and Defense Minister Moshe (Bogie) Ya’alon meet on June 13, 2014, as security forces search for three missing yeshiva students, feared kidnapped in the West Bank. (photo credit: Haim Zach/GPO/Flash90)

Brig. Gen. Motti Almoz, the commander of the IDF Spokesperson’s Unit, said Friday evening that security forces were doing everything possible to locate the youths.

Earlier Friday, US Ambassador in Israel Dan Shapiro was briefed on the fact that one of the three teenagers was a dual Israeli-American citizen.

Palestinian prisoners in Israel were celebrating the news of the feared kidnappings, according to Channel 2. Over 100 Palestinian prisoners have been on hunger strike to protest their detention without charge.

A senior Islamic Jihad official on Friday called on Palestinians to kidnap Israeli citizens, arguing that Israel had proven in the past that it was willing to negotiate the release of Palestinian security prisoners in exchange for the lives of its civilians.

Palestinian Islamists have repeatedly called to kidnap Israelis, including to use them as bargaining chips to extract the release of Palestinian security prisoners.

The Ezzedine al-Qassam Brigades,the armed branch of Hamas, issued a statement warning that “the occupier will never have security,” but without referring specifically to the missing three.

The Prime Minister’s Office said Friday that, since the beginning of the year, the Shin Bet has foiled 14 attempts to kidnap Israelis.

Netanyahu called the families of the three teenagers, urging them to stay strong, and telling them the State of Israel would do everything possible for their sons. He promised to keep them updated.

Netanyahu met Friday with Defense Minister Moshe Yaalon, Public Security Minister Yitzhak Aharonovitch, Gantz and the Shin Bet at the Defense Ministry headquarters in Tel Aviv for a security assessment.

The three students were reported missing Thursday night after witnesses said they had been seen hitching rides home at around 10 p.m. from their yeshiva in Gush Etzion.

The IDF spokesperson’s office said they lost contact with the three Thursday overnight.

“Since the morning, we have been engaged in operational activity designed to find [them] and bring them [back],” said Almoz. “Over the past several hours, there has been a very large intelligence effort to try and determine what happened with those youths since they disappeared.”

Facts that might interfere with the ongoing investigation, he said, were being withheld at this time.

Earlier Friday, Palestinian media reported a firefight between Israeli military forces and Palestinian gunmen in the South Hebron Hills region. According to a report in the Palestinian Ma’an news agency, large IDF forces raided the village of Yatta in the Hebron region and searched houses there. The military had set up road blocks in the area.

AFP contributed to this report.