Story highlights Palestinian news agency reports 12 people have been arrested

Netanyahu says Palestinian Authority has a "responsibility" to get them

Israeli security have orders to find teens, make sure they aren't moved

Missing teenagers were purportedly taken in settlements in the West Bank

Israel's prime minister on Saturday gave security forces the OK to use "all measures" at their disposal to find and free three teenagers believed kidnapped in an area of Jewish settlements in the West Bank.

The teens have been missing since late Thursday or Friday, having last been seen around Gush Etzion, according to Israel Defense Forces.

"(They were) kidnapped by a terror organization, there is no doubt about that," Prime Minister Benjamin Netanyahu said in a nationally televised address Saturday.

While it wasn't clear which group is behind the alleged abductions, Netanyahu stated explicitly that "it is the responsibility" of the Palestinian Authority to do something about the teens.

To that point, Netanyahu said he's asked the Palestinian Authority President Mahmoud Abbas "to do everything to help bring them back in peace."

Netanyahu said he's given security force leaders orders to locate the teenagers and prevent them from being moved to Gaza or any other place.

Already, dozens of Palestinians have been arrested in the southern part of the West Bank in connection with the search, and Israeli forces have been reinforced by a paratroop brigade, an Israeli military source said earlier Saturday. The official Palestinian news agency WAFA reported at least 12 people had been arrested in West Bank.

The IDF is looking at all scenarios as it seeks to identify who is behind the believed kidnapping, and it has not ruled out the possibility that the perpetrators will try to reach Gaza, the source said.

There is ongoing security coordination with the Palestinian security services, who understand that this "is not just some terror attack. It has substantial meaning to us," the source said.

A burned-out car is being examined for any possible connection to the teens' disappearance.

The deployment of military assets to search for the teens, and the swift presumption of kidnapping, are a reflection of the tensions that exist between Jewish settlers and Palestinians in the West Bank.

The expansion of Jewish settlements in the West Bank has been a lasting point of contention in the region.

It has altered the map of the Palestinian territories, making it more difficult to draw a contiguous Palestinian state as part of any peace agreement, according to critics.

The highly contentious issue of Israeli construction in the West Bank and East Jerusalem, which the Palestinians seek for a future state, has hurt peace efforts.