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.

IRAQ and SYRIA

Syrian rebel forces declared a new battle against government troops today, part of an escalation of violence which has undermined a ceasefire and threatens UN-brokered peace negotiations. [Reuters]

Rebels have attacked Syrian government forces in Latakia province today. [Reuters]  Syria’s main opposition group Riad Hijab has said that continuing with the peace talks is “unacceptable” while the government continues to bomb civilian areas and otherwise violate international law. [Reuters]

The EU this weekend called on Tehran to use its influence with Syria to help advance peace negotiations after the fragile talks resumed in Geneva. [Wall Street Journal’s Laurence Norman and Sam Dagher]

“Despite talk of a ‘regime’ and ‘opposition,’ Syria today is a mosaic of tiny fiefs.” Thanassis Cambanis discusses Syria’s future, calling it a “black hole of instability.” [New York Times]

Carter in Iraq. Defense Secretary Ash Carter arrived in Baghdad today for talks with Iraqi leaders on how to strengthen the fight against the Islamic State, as the country’s armed forces work toward taking back Mosul from the militant group. US efforts to help the Iraqi military will likely include deploying a “small number” of additional American troops, say officials. [AP; Reuters]

The Islamic State’s revenue has dropped by almost a third since mid-2015, the result of a loss of territory. The group has introduced a range of new taxes in response, according to research group, IHS. [AFP]

The US has increased “cyber operations” against ISIS, intended to disrupt the militant group’s “command-and-control and communications.” Shane Harris and Nancy A. Youssef provide the details at The Daily Beast.

Kurdish militants attempting to escape into Syria from the Turkish border town of Nusaybin were killed by Turkish security forces, sources reported today. [Reuters]

“Desperate” conditions have been reported in Yarmouk, a Palestinian refugee camp in Damascus, Syria, by the UN Palestinian refugee agency, UNRWA. Around 10,000 civilians are reportedly trapped in the camp. [AP]

Israeli Prime Minister Benjamin Netanyahu declared that Israel will never return the occupied Golan Heights to neighboring Syria, convening symbolic meeting of his cabinet on a mountain there. [Haaretz; Washington Post’s William Booth]

UK firm Aegis Defence Services employed mercenaries from Sierra Leone to work in Iraq, according to former director of the firm James Ellery, adding that checks were not undertaken to make sure those recruited were not former child soldiers. The mercenaries were used to reduce the costs for the American presence in Iraq. [The Guardian’s Alice Ross]

EUROPEAN TERROR THREAT

UK authorities have released on bail one of five people arrested last week on suspicion of plotting terrorism; a source said that the arrests were linked to the Paris and Brussels attacks. [Reuters]

The Brussels attacks have provided “new impetus” for greater intelligence sharing between European nations, Julian E. Barnes and Stephen Fidler report, citing “long-standing” problems including security agencies that “jealously guard their secrets and sources.” [Wall Street Journal]

German authorities and airport officials called for a review of security measures at airports, amid mounting concerns over existing procedures and the ability to detect weapons. [Wall Street Journal’s Ruth Bender and Robert Wall]

Thousands of people took to the streets of Brussels over the weekend, in a protest against “terror and hate.” [BBC]

SAUDI ARABIA

President Obama is due meet Saudi Arabia’s King Salman in Riyadh on Wednesday amid increasing pressures on the nations’ relationship, reports Michael D Shear, including disagreements over Iran, the fight against Islamic State, Syria and fighting in Yemen, despite which the countries “still need each other.” [New York Times]

“Did the Saudis play some role in supporting the hijackers responsible for the attacks on September 11th?” The “28 pages,” a section of a congressional report on 9/11 that is subject to a renewed push for declassification, may reveal the answer to this question, suggests Kristin Donnelly, though it is unlikely that it will be published before President Obama’s visit to Saudi Arabia on Wednesday. [NBC News]

Saudi Arabia has threatened to sell off billions of dollars’ worth of US assets if Congress passes a bill that would allow the Saudi government to be held responsible in American courts for any role in the 9/11 terror attacks. The Obama administration has lobbied Congress to have the bill blocked on the ground that it would put US citizens at legal risk overseas. [New York Times’ Mark Mazzetti; Financial Times’ Geoff Dyer and Simeon Kerr]

GUANTANAMO BAY

Saudi Arabia has accepted nine Yemeni Guantánamo Bay detainees, all of whom had been at the detention center since 2002 and none of whom have been charged with a crime. They have been transferred to Saudi Arabia’s rehabilitation program which aims to help jihadists transition back into society. [Miami Herald’s Carol Rosenberg]  Following the men’s release, 80 prisoners remain at Guantánamo Bay. [NPR’s Merrit Kennedy]

Environmental health experts will not complete their tests at Camp Justice until the fall, the head of Navy Medicine East Rear Adm. Kenneth Iverson has said. A preliminary report from the Navy and Marine Corps Public Health Center found dangerous chemicals including mercury and arsenic at the Camp. This may explain why the judge due to take over the case of Majid Khan has postponed the next hearing from May 11-12 to August 30, suggests Carol Rosenberg, though the judge’s order cites “the interest of justice.” [Miami Herald]

AFGHANISTAN

“Intense” fighting in Afghanistan continued over the weekend as government forces and the Taliban attempted to take the strategic city of Kunduz. [Al Jazeera’s Hashmat Moslih]

The number of civilians being killed by Afghan government forces is rising, according to a UN report, children making up a third of those killed this year. [New York Times’ Mujib Mashal; The Guardian’s Sune Engel Rasmussen]  The Afghan national army is using schools refurbished using British aid money as bases, including one in Chahe Anjir in the Nad Ali district which is still attended by pupils. [The Guardian’s Sune Engel Rasmussen]

OTHER DEVELOPMENTS

A Russian fighter plane intercepted a US Air Force reconnaissance plane over the Baltic Sea on Thursday, US officials reported on Sunday, the second incident of this nature in a week. Russia has claimed it was responding to an unidentified target approaching its border. [Wall Street Journal’s Gordon Lubold et al]

Most of the presidential candidates are unaware that war is looming “due to a fundamental change in the international system,” says Mark Helprin, listing the current trends that will eventually see “three great powers – China, Russia, the US – each with a complex and shifting system of alliances in unstable areas subject to proxy wars and opportunistic territorial expansion.” [Wall Street Journal]

A tunnel reaching several hundred meters into Israel’s territory from the Gaza strip has been found and “neutralized” by the Israeli military, which says that the tunnel was constructed by Hamas, the Palestinian militant group, in order to “infiltrate Israel and execute terror attacks.” Hamas has said it is an “old” tunnel. [BBC; AP]

Businesses are anxiously awaiting the Privacy Shield agreement to be put in place, reports Katie Bo Williams, citing concerns of a chilling effect on transatlantic trade. [The Hill]

UK foreign secretary Philip Hammond made a “surprise” visit to Libya’s capital, Tripoli, today, to support the UN-backed unity government. French and German ministers gave their backing a few days ago. [AFP; BBC]

Yemen peace talks have been delayed amid ongoing fighting in breach of the ceasefire. The talks had been due to begin in Kuwait today, but delegations representing the Houthis and the party of ex-president Ali Abdullah Saleh remain in Yemen’s capital, Sana’a. Officials have said that they are now expected to arrive in Kuwait tomorrow. [Reuters]

Boko Haram attacked Nigerian soldiers in the northeastern Kareto area this morning. [Reuters]

China dispatched a military plane to one of its manmade islands in the South China Sea yesterday. For what is believed to be the first time, China’s Defense Ministry openly acknowledged the mission via its website. [AP]

North Korea is preparing a fifth nuclear test, South Korea’s President Park Guen-hye has reported, citing “signs.” [Wall Street Journal’s Alastair Gale]  Deputy Secretary of State Antony Blinken has promised a “strong response” to any further tests. [Reuters’ Minami Funakoshi]