* Israeli army raids Palestinian cities of Ramallah, Nablus
* Abbas says has no information Hamas abducted teens
* Four Palestinians killed since Israeli search began (Adds Palestinians seek U.N. Security Council meeting)
By Ali Sawafta
RAMALLAH, West Bank, June 22 (Reuters) - Israeli troops killed two Palestinians on Sunday, Palestinian medics and a militant group said, as Israel pressed on with its crackdown on Hamas, the Islamist group it accuses of abducting three Israeli teens.
Soldiers entered several Palestinian cities and villages in the occupied West Bank, rounding up six suspected militants, the Israeli military said.
Israel has said its West Bank operation is twofold - to find Gil-Ad Shaer and U.S.-Israeli national Naftali Fraenkel, both aged 16, and Eyal Yifrah, 19, who went missing near an Israeli settlement on June 13, and to deal a substantial blow to Hamas.
Hamas, sworn to Israel's destruction, has neither denied nor confirmed involvement in the disappearance of the youths.
Israeli Prime Minister Benjamin Netanyahu, in public remarks to his cabinet on Sunday, said Israel had conveyed its evidence against Hamas to several countries and would soon make it public. He defended Israel's military action in the West Bank.
"We have no intention of deliberately hurting anyone, but our forces are acting as necessary for their self-defence and, on occasion, there are fatalities or casualties on the Palestinian side," Netanyahu said.
Cautioning that Israel was "bringing the situation towards an explosion", the Palestinian Authority said it had launched efforts to convene an urgent session of the U.N. Security Council to try to end the offensive.
The military has so far searched some 1,350 sites in the West Bank and detained more than 330 Palestinians. The raids have triggered street clashes in which four Palestinians have been killed.
During a raid in the city of Nablus, Israeli soldiers fired at stone-throwing Palestinians, killing Ahmad Famawi, 26, residents and medics said.
The military said its soldiers fired at a suspect who approached them without responding to calls to stop. The incident is being investigated, it said, though an "initial inquiry suggests the suspect was mentally unstable".
In Ramallah, the Islamic Jihad militant group said one of its members was killed by Israeli gunfire. The Israeli military said it was investigating the incident.
ABBAS CHALLENGES NETANYAHU
The crisis has put pressure on a unity pact between Western-backed Palestinian President Mahmoud Abbas and rival Hamas.
Abbas has condemned the abduction of the three Israelis, and his security forces have been helping in the search. But he has also called the Israeli sweeps collective punishment.
Abbas's security cooperation with Israel touched off a rare protest against Palestinian police in Ramallah, the seat of his government, on Sunday.
Chanting "collaborators", dozens of people hurled rocks at a police station and damaged three police cars when policemen remained inside the building rather than joining protesters in confronting Israeli troops who entered the city, witnesses said.
In an interview with Israel's Haaretz newspaper, Abbas said he had no credible information Hamas was behind the kidnappings.
"I do not intend to punish anyone based off suspicions or because Netanyahu claims something. When Netanyahu has such information, he needs to update me and we will take care of the matter according to our own laws," he said. (Reporting by Ali Sawafta, Writing by Ari Rabinovitch, Editing by Jeffrey Heller and Rosalind Russell)