WASHINGTON — After a day and evening in White House talks with President Barack Obama, Israeli Prime Minister Benjamin Netanyahu and Palestinian President Mahmoud Abbas were to sit down together today for the first of what American officials hope will be a series of meetings that lead in a year's time to an agreement on the creation of a Palestinian state.

Mediated at the State Department by Secretary of State Hillary Rodham Clinton and special Mideast peace envoy George Mitchell, the two leaders' discussions face numerous obstacles, not the least of which is renewed violence by those opposed to the goal of an independent Palestine and secure Israel.

Gunmen from the militant Palestinian Hamas group, which opposes the talks, killed four Israeli residents of a West Bank settlement on Tuesday as Netanyahu, Abbas and the leaders of Egypt and Jordan convened in Washington. And on Wednesday, hours before the leaders were to eat dinner together at the White House, gunmen wounded two Israelis as they drove in their car in another part of the West Bank. Hamas claimed responsibility.

After the first attack, security forces loyal to Abbas, who heads a moderate government in the West Bank, quickly rounded up 250 Hamas members and supporters.

Netanyahu said the violence would not disrupt the talks.

Israelis "recognize that another people shares this land with us," Netanyahu said Wednesday. But he said any agreement must guarantee Israel's security and could not be a repeat of Israel's withdrawals from Gaza and Lebanon, where territory was seized by Iran-backed militants who launched attacks on Israel.

Abbas joined Netanyahu in declaring that it was time to seize the moment, but added needs to free all Palestinian prisoners and freeze all settlement construction on land Palestinians want for their future state.