* Netanyahu blames Hamas for abductions, hopes to weaken it
* Military raids trigger confrontations in West Bank towns
* Palestinians accuse Israel of collective punishment
By Ali Sawafta
RAMALLAH, West Bank, June 17 (Reuters) - Israel's security cabinet decided on Tuesday to widen a crackdown on Hamas in the West Bank after troops detained more than 40 members of the Palestinian Islamist group in sweeps conducted in tandem with a search for three missing teenagers.
Israel accuses Hamas of kidnapping the three youths after they left their religious school in a Jewish settlement on Thursday. Hamas, which seeks Israel's destruction, has neither claimed nor denied responsibility for their disappearance.
The Israeli army has launched house-to-house searches, round-ups of suspects and interrogations in Hebron, a Hamas stronghold, and then in other parts of the occupied West Bank, in a mobilisation on a scale not seen in years.
"We are turning Hamas membership into a ticket to hell," Naftali Bennett, a far-right member of Prime Minister Benjamin Netanyahu's cabinet, told Israel's Army Radio on Tuesday.
The Palestinian Information Ministry accused Israel of inflicting collective punishment - a charge echoed by several international human rights groups.
"An entire population is being held hostage to the whims of the Israeli occupation," the Palestinian ministry said.
Israel has said it does not know if Gil-Ad Shaer and U.S.-Israeli national Naftali Fraenkel, both aged 16, and Eyal Yifrah, 19, are alive or what their captors' demands might be.
At its meeting on Tuesday, Netanyahu's security cabinet agreed to make more arrests, put up roadblocks and turn Palestinian houses into military observation posts to increase pressure on Hamas, a political source said.
An Israeli official said ministers had also debated a proposal to deport West Bank Hamas leaders to Gaza.
Earlier, the army said it had detained 41 Hamas militants in overnight raids, raising to more than 200 the number arrested since Friday. Israel officials acknowledged the operation was two-fold - recovering the missing teenagers and weakening Hamas.
"PURSUED, PARALYSED AND THREATENED"
"As long as our boys remain abducted, Hamas will feel pursued, paralysed and threatened. We are committed to resolving the kidnapping and debilitating Hamas terrorist capacities, its infrastructure and its recruiting institutions," said Lieutenant-Colonel Peter Lerner, an Israeli military spokesman.
Israel showed photographs of what it said were hundreds of weapons, including guns, seized at some of the detainees' homes.
Western-backed Palestinian President Mahmoud Abbas has condemned both the kidnappings and the Israeli raids.
Mirroring scenes played out elsewhere in the West Bank, Israeli soldiers filed through a street of shuttered homes and shops in the town of Jenin on Tuesday, lobbing stun grenades and firing rubber bullets at Palestinians who threw rocks at them.
Israeli and Palestinian security sources said soldiers and police had wounded five Palestinians in Jenin and in confrontations near the cities of Ramallah and Nablus.
In the Gaza Strip, Israel's air force bombed four militant targets early on Tuesday in response to rocket fire at southern Israel. There were no reported casualties in those incidents.
On Monday, Netanyahu said the effort to retrieve the three teenagers was complicated and that Israelis "must be prepared for the possibility it could take time".
Many Israelis have shown solidarity with the teens' families on social media sites and have held public prayer vigils.
One of the youth's mothers, Rachel Fraenkel, thanked her compatriots on a nationally televised broadcast, saying: "We just wish to hug our children home, Naftali, Eyal Gil-Ad. We love you, we miss you, please be strong, hold on, be strong."
Giora Eiland, a retired Israeli general and former national security adviser, said the abductions provided an opportunity to target Hamas in operations that could undermine a new Palestinian unity government formed after Abbas reconciled with his Islamist rivals in April after years of feuding.
Infuriated by the surprise intra-Palestinian alliance, Netanyahu called off U.S.-sponsored peace talks with Abbas.
"The fragile links between the (Abbas-led Palestinian) Authority and Hamas could become more of a crack," Eiland told Israel Radio, a day after the Islamists condemned as a "knife in the back" PA efforts to help the Israelis locate the teenagers. (Editing by Jeffrey Heller and Gareth Jones)