As U.S.-backed Arab and Kurdish forces broke into the Islamic State group's bastion of Raqa on Tuesday for the first time, here are five facts about the city in northern Syria:

Gulf states Saudi Arabia, Bahrain and the United Arab Emirates as well as Egypt on Monday cut ties with Qatar over accusations it supports extremism, in an unprecedented regional crisis.   

Saudi Arabia, Bahrain and the United Arab Emirates severed ties with Gulf neighbor Qatar on Monday over accusations it supports extremism, with Egypt and Yemen following suit. 

Its vaunted air force destroyed, its army humbled -- the Six-Day War of 1967 dealt Egypt a shock it has yet to overcome and spelled the end of its pan-Arab hopes for regional dominance.

They are veterans of Syria's rebellion, trying for years to bring down President Bashar Assad. But these days they're doing little fighting with his military. They're struggling to find a place in a bewildering battlefield where several wars are all being waged at once by international powers.

Syria's civil war has become a madhouse of forces from Turkey, the United States, Syrian Kurds, the Islamic State group, al-Qaida as well as Assad's allies Russia, Iran, Lebanon's Hezbollah, Iraqi and Afghan Shiite militias — all with their own alliances and agendas.

Israel and Arab countries have fought several conflicts since the Jewish state was created in 1948, without counting its offensives in Lebanon and the two intifadas, or uprisings, in occupied Palestinian territories:

- The 1948 war - The first war breaks out on May 15, 1948, the day after the proclamation of Israel's statehood by David Ben-Gurion.

The Arab-Israeli Six-Day War erupted early on Monday, June 5, 1967, a morning that saw heavy Israeli bombing of Egyptian air bases near Cairo and in the Suez desert.

Relations between the United States and Germany veered further toward crisis on Tuesday as President Donald Trump complained about the U.S. trade deficit with Germany and said it must pay more for the NATO military alliance.

U.S. President Donald Trump's performance at a "shocking" NATO summit has dealt a major blow to the alliance and may hand a win to Vladimir Putin, analysts say.

Washington has announced a bumper arms deal with Saudi Arabia, heralding the package as a major boost to long-standing security ties and a way to further isolate Iran.