JERUSALEM -- Israel's defense minister said Saturday he believes the three Jewish seminary students who went missing in the West Bank were kidnapped by Palestinian militants and that the military is determined to rescue the teens.
The three disappeared late Thursday in the West Bank, reportedly while hitchhiking. An official has said one is a U.S. citizen.
Israeli troops have scoured the southern West Bank, near the Palestinian city of Hebron, and have arrested more than a dozen Palestinians.
If confirmed that the three teenagers, ages 16 and 19, were seized by Palestinian gunmen, it would be the biggest kidnapping by such militant groups in recent memory in the West Bank.
Israeli-Palestinian tensions already were strained at the time of Thursday's suspected kidnapping, in part because of the recent formation of a Palestinian unity government that has the backing of the Islamic militant Hamas.
Israeli Defense Minister Moshe Yaalon said Saturday that Israel has thwarted dozens of kidnapping attempts by militants, including 14 so far this year.
"It appears this event slipped under our radar, but we will not rest until we free the youths and put our hands on the terrorists who are responsible for this operation," Yaalon said.
He added: "As long as we don't know otherwise, our working assumption is that they are alive."
Israeli authorities clamped a partial gag order on the case. Israeli media have been reporting the incident almost nonstop, casting aside regular programming.
On Saturday, local media published the names of the teens and their home communities, two West Bank settlements and one in Israel.
Israel's government held Palestinian President Mahmoud Abbas responsible for the fate of the teens.
"The current crisis is a direct result of the decision by Palestinian President Mahmoud Abbas to force a political alliance with these Hamas terrorists," said Mark Regev, a government spokesman.
Hamas, branded a terror group by the West for its attacks aimed at civilians, has been involved in kidnappings of Israeli soldiers in the past. The group routinely claims responsibility if involved in an attack, but has not claimed Thursday's suspected kidnappings.
Palestinian officials also rejected Israel's attempts to blame Abbas, noting that Israel retains overall security control in the West Bank.
Despite the charged rhetoric, Palestinian security forces were cooperating with Israeli counterparts in trying to find the teens, a Palestinian official said.
Israeli forces detained more than a dozen people in connection to the case and are examining local security camera footage, a second official said.
They spoke on condition of anonymity because there were not authorized to brief journalists.
Abbas has said security coordination in the West Bank between Israel and the Palestinians, usually aimed at tracking down Islamic militants, will continue despite the unity government.
Meanwhile, three different claims of responsibility emerged in the West Bank, though it's not clear if any are authentic.
In one leaflet, a group portraying itself as a branch of an al-Qaida splinter group said it kidnapped the three to avenge the killing of three fighters by Israeli security forces earlier this year.
Militant groups, including Hamas, frequently call for the abduction of Israelis.
Israel's military has warned soldiers and civilians not to accept rides from strangers, but hitchhiking remains common.
Two of the teens are from settlements in the West Bank, territory Israel captured from Jordan in the 1967 Mideast war and that Palestinians are demanding as part of their future state along with the Gaza Strip and east Jerusalem.
Hamas ruled Gaza for seven years, after violently taking over the territory from the Palestinian Fatah group in 2007, and remains the de facto power there despite the unity deal.
Militants in Gaza fired a rocket at southern Israel early Saturday, the Israeli military said, adding that nobody was hurt in the attack.
Israel retaliated with an airstrike on "a terror activity site and a weapon storage facility" in Gaza, the military said. There were no reports of injuries.