TEL AVIV, ISRAEL — Israel is beefing up boots on the ground in a West Bank incursion of paratroopers, infantry and special forces dubbed “Return Our Sons,” an operation aimed at recovering three teens abducted while hitchhiking on June 12.

As of late June 15, more than three Israel Defense Forces (IDF) brigades, Shin Bet security teams and elite units were operating primarily in the area south of Hebron, where officials suspect Hamas operatives associated with Hamas may be holding the captives.

With select reserve forces taking up positions elsewhere in so-called Area C where Israel maintains full control of the disputed territory, the operation marks the largest West Bank incursion since Israel’s 2002 Defensive Shield campaign, sources here say.

“It’s a substantial operation,” an IDF officer told Defense News of the more than three brigades of paratroopers, Nahal and Kfir infantry and elite units already deployed.

He declined to speculate on how long the operation would last if forces were unable to locate the missing Israelis, one of whom holds US citizenship.

The operational assumption is that the captives are still in the West Bank, but officials are not ruling out other scenarios.

Prime Minister Benjamin Netanyahu said June 15 that Israel knew “for a fact” that Hamas operatives abducted the three teens. Nevertheless, he vowed to hold Palestine Authority (PA) President Mahmoud Abbas accountable for terror emanating from the territory now administered by his new consensus government backed by Hamas.

“Instead of abiding by his international obligation to disarm Hamas, President Abbas has chosen to make Hamas his partner. Israel holds the PA and President Abbas responsible for any attacks against Israel that emanate from Palestinian controlled territory,” Netanyahu warned.

Netanyahu rejected as “patently absurd” PA claims that it could not be expected to enforce security in an area under full Israeli control.

“When an attack takes place in Tel Aviv or in London or in New York ... the question is not where the attack takes place. The question is where it originated,” Netanyahu said.

“The kidnappers in this case set out from territory controlled by the PA, and the PA cannot absolve itself of its responsibility,” he insisted.

But contrary to Netanyahu’s threatened action against Abbas and the new consensus government in Ramallah, US Secretary of State John Kerry urged Israel to cooperate with PA authorities in the West Bank.

In a June 15 statement, Kerry said Washington was still “seeking details on the parties responsible for this despicable terrorist act, although many indications point to Hamas’ involvement.”

Kerry called for “full cooperation between the Israeli and Palestinian security services” in locating and returning the youths.

And while coordination between Israeli and Palestinian security forces was continuing as of late June 15, defense sources here warned against escalating confrontation with Abbas and his Fatah-led forces.

An IDF officer noted that the PA security forces were the first to locate and report a burned out vehicle near Hebron thought to transport the Israeli teens.

“They’re doing what they can for their own interests. They realize the significance of their role in all this; the more supportive they are, the sooner we can declare an end to this operation,” a top Israeli officer told Defense News.