Before the start of business, Just Security provides a curated summary of up-to-the-minute developments at home and abroad. Here’s today’s news.

YEMEN

A Saudi-led airstrike hit a camp for displaced persons. At least 40 civilians were killed and about 200 wounded when the strike hit the camp in the country’s northern Hajjah province yesterday afternoon. The incident is thought to be the deadliest single episode involving civilians since the Saudi-led campaign to push back Houthi rebels began last Thursday. Saudi Arabia did not immediately respond to allegations of civilian fatalities although a spokesperson for the coalition is expected to address the subject at a briefing. [The Guardian’s Kareem Shaheen; New York Times’ Saeed al-Batati and Rick Gladstone]

Saudi-led airstrikes continue. Air raids targeted Houthi militia locations across Yemen overnight, striking Sana’a, the group’s stronghold in Sa’adeh and the town of Yarim. [Reuters’ Sami Aboudi and Mohammed Mukhashaf]

Saudi-led naval forces imposed a blockade on Yemeni ports yesterday, a move said to be aimed at preventing weapons and fighters from bolstering the Houthi ranks. [Wall Street Journal’s Hakim Almasmari and Ahmed al-Omran]

Iran has sent aid to Yemen, the first shipment of aid by Tehran since the launch of a Saudi-led coalition of Sunni Arab states against Shi’ite Houthi rebels in the country. [AP

China has evacuated more than 600 nationals from Yemen, with over 500 leaving the coastal city of al-Hodayda aboard a navy frigate. [Reuters’ James T. Areddy]

Walter Pincus tries to separate “fact from fiction” in Yemen and Iraq, noting that despite the need for the U.S. to be prepared for shifting alliances in the region, it is important to be able to tell “reality from propaganda.” [Washington Post]

Check out Haaretz for live updates as the situation in Yemen develops. 

IRAN NUCLEAR DEAL

Talks have entered their final day as the P5+1 and Iran attempt to reach a framework agreement in Lausanne ahead of the self-imposed 6 p.m. EDT deadline. Officials say the parties are close to a general statement agreeing to continue talks in a new phase, supplemented by documents that include more detailed understandings. Russian Foreign Minister Sergey Lavrov is on his way back to Lausanne, a positive sign for the negotiations as the foreign minister left talks yesterday saying he would return if an accord were imminent, report the AP’s George Jahn and Matthew Lee.

Sticking points remain in this latest round of negotiations, particularly on enrichment research and the timeline for lifting Iran sanctions. [Reuters’ Louis Charbonneau et al] Secretary of State John Kerry told CNN after yesterday’s discussions that there is “a little more light … but ​there are still some tricky issues,” report Elise Labott and Ben Brumfield.

It is unclear whether Iran’s supreme leader will sign off on the concessions required for a deal, according to Western officials. [Wall Street Journal’s Jay Solomon and Laurence Norman]

Saudi Arabia is “lashing out against” Iran as a nuclear deal emerges, with the country expected to speed up efforts to develop a nuclear weapon, in addition to leading airstrikes against the Iran-backed Houthi rebels in Yemen, reports David D. Kirkpatrick. [New York Times]

Failure to reach agreement, now or later, is still a possibility; Michael Crowley explores the implications of the nuclear diplomacy failing. [Politico]

Bret Stephens is critical of the emerging deal and argues that the administration “refuses to negotiate openly, lest the extent of its diplomatic surrender to Iran be prematurely and fatally exposed,” in a Wall Street Journal op-ed.

Securing an Iran deal must remain an American priority, even if it is inconsistent with backing Saudi’s campaign in Yemen, argues Roger Cohen. [New York Times]

A majority of Americans support a deal with Iran that would limit the country’s nuclear program in exchange for relaxing sanctions on Tehran, according to a new Washington Post-ABC News poll.

IRAQ and SYRIA

The Pentagon has denied reports that a U.S. drone strike on Tikrit killed two Iranian military advisers working in a supportive role as Iraq attempts to retake the city. Iran’s Revolutionary Guard Corps posted an online statement claiming the two men were killed on March 23; the U.S. denies carrying out any strikes in the area on that date. [The Guardian’s Spencer Ackerman]  While mishaps are “certainly a high risk” for the U.S.-led coalition, officials say the accusations of misdirected strikes “appear to be driven by a political agenda,” writes Jamie Dettmer. [The Daily Beast]

The Islamic State’s grip on Tikrit appears stronger than the Iraqis acknowledge, and the group holds much more territory than has been admitted by the military, writes Rod Nordland. [New York Times]

Shi’ite militia fighters in Tikrit claimed to have received assurances from the Iraqi prime minister that there would not be any further U.S.-led airstrikes on the city, allowing for them to rejoin the battle, reports Loveday Morris. [Washington Post]

The Canadian parliament has approved a one-year extension to military operations against the Islamic State, expanding its role to include strikes in Syria. [AP’s Rob Gillies]

The U.S. training of moderate Syrian oppositions rebels is feared to be “too little, too late” by many, and “dithering and bureaucratic confusion” in the White House may add to the challenge of succeeding in the mission. [Foreign Policy’s Sean D. Naylor]

Syrians in Idlib await “anxiously” to discover who will govern them and in what manner, following the victory of Islamist insurgent groups, including the Nusra Front, over the city last weekend. [New York Times’ Anne Bernard]

U.S.-led airstrikes continue. U.S. and coalition forces carried out seven strikes against Islamic State targets in Iraq on March 29. [Central Command]

ISRAEL and PALESTINE

Israeli leader Benjamin Netanyahu must take the initiative to counter the “revived de-legitimization movement” targeting Israel, which has gained “new momentum” in light of Netanyahu’s campaign statement on Palestinian statehood, argue Dennis Ross, David Makovsky and Ghaith Al-Omari. [Politico Magazine]

Palestinian discontent with President Mahmoud Abbas is rising, with many questioning if the Palestinian leader can deliver on the peace process. [New York Times’ Dia Hadid]

OTHER DEVELOPMENTS

The U.S. is supportive of the creation of an Arab joint-military force aimed at countering the numerous security threats in the Middle East, and the Pentagon will cooperate with it where U.S. and Arab interests align, said Defense Secretary Ash Carter yesterday. [Reuters’ David Alexander] 

Lawyers for five Afghan detainees at Guantanamo Bay have asked for their release in a letter to the Obama administration, citing the conclusion of the combat mission in Afghanistan and noting that “the only possible justification for detention” has come to an end. [Miami Herald’s Carol Rosenberg] 

Two men crashed into a gate at the NSA headquarters, resulting in a shooting that left one person dead and a law enforcement officer injured. The FBI does not suspect a terrorist link and early reports suggest that the armed men took a wrong turn and did not intend to enter the facility. [The Daily Beast’s Shane Harris] 

NATO and the EU should find ways to cooperate more closely, and it is critical that European nations spend more on defense, according to NATO Secretary General Jans Stoltenberg speaking before the European Parliament yesterday. [Wall Street Journal’s Naftali Bendavid]

In the “increasingly complicated web of alliances” in the Middle East and elsewhere, Egypt is being caught in the middle as relations between Saudi Arabia and Russia become increasingly hostile. [Washington Post’s Adam Taylor]

Secretary of State John Kerry has ordered an internal review of the department’s record keeping, in the wake of revelations that former Secretary of State Hillary Clinton used a private email account and server while in office. [AP’s Bradley Klapper]

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