A suicide attacker in a vehicle packed with explosives killed at least five people at the interior ministry in Baghdad on Monday as a worsening political standoff stoked sectarian tensions.

The blast, which left dozens wounded, came just days after the capital was struck by its deadliest violence in more than four months and as U.S. Vice President Joe Biden urged dialogue between Iraqi politicians to resolve their differences.

Israeli soldiers detained five Palestinians trying to infiltrate the Jewish state from the Gaza Strip on Sunday, an Israeli military spokeswoman said.

"This evening the soldiers spotted and arrested three Palestinians who were trying to cross the security barrier separating Israel from the central part of the Gaza Strip" controlled by the Hamas movement, she told Agence France Presse.

Gunmen shot dead an intelligence chief on Sunday in the port of Aden in south Yemen, a police official said, blaming the attack on al-Qaida.

The assailants intercepted the vehicle carrying Colonel Hussein Shabibi, head of internal security in the city's Sheikh Othman district, and shot him dead before making good their escape in a car, the official said.

Israel's defense ministry said on Sunday that the United States has agreed to provide it with an additional 235 million dollars to finance its rocket defense system.

"The aid from the American Congress is a supplementary step in the reinforcement of Israeli-American relations in the area of defense," Defense Minister Ehud Barak said in a statement.

U.S. Vice President Joe Biden urged leaders of Iraq's feuding political and sectarian factions Sunday to convene a "dialogue" to head off a worsening political crisis.

Biden, President Barack Obama's pointman on Iraq, has made a flurry of calls to Iraqi leaders this week, urging them to mend their fences after the Shiite president, Nouri al-Maliki, accused his Sunni vice president, Tareq al-Hashemi, of hiring bodyguards to run a death squad.

The United States is mulling a far more subdued role in Iraq after pulling its troops out, and has no intention to send its forces back in despite a spike in violence, The New York Times reported Sunday.

U.S. officials told the Times that President Barack Obama was adamant that the United States would not send troops back to Iraq, adding that even an American military presence likely would not have prevented the political crisis and coordinated attacks plaguing the country days after a U.S. pullout.

Iraqi Vice President Tareq al-Hashemi, who is charged with running a death squad, told Agence France Presse in an interview on Sunday he would not go to Baghdad to stand trial and raised the prospect of fleeing Iraq.

Hashemi, holed up at an official guesthouse of Iraqi President Jalal Talabani in the country's autonomous Kurdish region, acknowledged his guards may have carried out attacks, but he has steadfastly denied any involvement.

The Arab League must bring the U.N. into the effort to stop Syria's bloody crackdown on protesters, the top opposition leader said Sunday, as security forces pressed ahead with raids and arrests around the country.

Burhan Ghalioun, the Paris-based leader of the Syrian National Council, made the plea as Arab League officials were setting up observer teams, part of their plan to end nine months of turmoil that has killed more than 5,000 people, according to the U.N.

Gaza militants have fired two rockets and two mortars at southern Israel, none of them causing any injuries or damage, the Israeli military said on Sunday.

"We identified two rocket launches from Gaza at Israel to the Eshkol and Shaar Hanegev regions Saturday night," a spokeswoman told Agence France Presse, adding two mortars were fired at Israel the evening before.

Iran stands ready to expand its military and security ties with Iraq, its armed forces chief of staff said Sunday, a week after the exit of U.S. forces from the neighboring Arab country.

General Hassan Firouzabadi hailed the "forced departure" of the U.S. and allied forces that he said "was due to the resistance and determination of the Iraqi people and government," the state Islamic Republic News Agency reported.