Updated

Israeli soldiers searched the West Bank on Friday for three missing teenagers from nearby settlements, one of them a U.S. citizen, amid fears Palestinian militants abducted them, authorities said.

Israel police spokesman Micky Rosenfeld said one of the missing teens called police to say the three had been kidnapped, without giving additional details. Prime Minister Benjamin Netanyahu blamed the Palestinian Authority for their disappearance without elaborating, saying he held the government responsible for their safety.

Netanyahu told the teens' families that Israel is "making every effort" to find them, his office said in a statement.

Palestinian authorities could not be reached for comment and no one immediately claimed responsibility for the teens' possible abduction.

Two Israeli defense officials said authorities believed the teens likely were kidnapped by Palestinian militants, without elaborating. They spoke on condition of anonymity as they were not allowed to brief journalists.

Brig. Gen. Motti Almoz, a military spokesman, said that military and intelligence forces were involved in the search for the missing teens.

"The main mission is to ensure their return," Almoz said. He refused to offer any other details, saying it would compromise the operation.

Tsuri Tsuf, a spokesman for a settlement where one of the teens is from, told Israel's Channel 10 television that his community was "greatly worried" and gathered to pray for the safety of the youths. The station reported the teenagers hitched a ride the night before from their Yeshiva, or religious seminary, and had not been seen since.

Authorities found a burned-out car during their search that investigators were examining, local media reported.

Israel's Shin Bet intelligence agency initially imposed a gag order Friday morning blocking local media from reporting on the incident. Later, an official familiar with the investigation told The Associated Press that one of the teens was an American and that Israeli authorities notified U.S. Ambassador Dan Shapiro. The official spoke on condition of anonymity as he wasn't authorized to publicly brief journalists.

The three 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.

If Palestinians abducted the teens, it would be the first serious incident to challenge relations with Israel since the formation of a Palestinian unity government earlier this month, led by President Mahmoud Abbas' Fatah party and backed by the Islamic militant group Hamas. The move was meant to end a crippling rift between Abbas and Hamas after a violent split between the rival Palestinian groups in 2007. Israel and the West consider Hamas a terror group because it has carried out suicide bombings and other deadly attacks targeting civilians.

U.S. Secretary of State John Kerry called Abbas to talk about the missing teenagers and likely will call Netanyahu as well, a senior State Department official said. The official was not authorized to discuss the matter by name and spoke on condition of anonymity.

Hamas frequently calls for the abduction of Israelis. The Israeli military has said it has foiled multiple Palestinian kidnapping attempts in recent years and warns soldiers and civilians not to accept rides from strangers. Despite the warnings, hitchhiking remains common in Israel.

While such incidents are relatively rare, it would not the first instance of Palestinians abducting Israelis.

Last year, a Palestinian lured an Israeli soldier to a village in the West Bank and killed him with the intention of trading the body for his jailed brother. And in 2001, a Palestinian woman lured an Israeli teenage boy over the Internet to the West Bank where he was killed by waiting Palestinian gunmen.

The woman, Amna Muna, was released in 2011 along with over a thousand other Palestinian prisoners in exchange for a single Israeli soldier, Gilad Schalit, held captive in Gaza by Hamas-allied militants for more than five years.