Summary:

The situation is fluid to say the least, but as far as we can tell this is what has happened tonight so far:

1. Sirens go off in Golan Heights 2. Loud explosions heard Then blame-game begins... 3. AP: The Syrian Observatory for Human Rights reported Wednesday that Israel has attacked targets of the Syrian military on the outskirts of Quneitra. 4. AP: Activists reported rocket fire from Israel into southern Syrian just before midnight Wednesday. 5. AP: The Israeli army says it is investigating and has no further details. 6. IDF report that Iranian Quds force fired 20 rockets towards forward IDF positions on Golan Heights. 7. According to al-Mayadeen (pro-gov) 10 positions of the Israeli Army were shelled with rockets, and several vehicles were targeted with guided missiles. 8. The IDF views this event with great severity and remains prepared for a wide variety of scenarios. 9. Exchanges continue... 10. Israeli jets fire on Damascus; shelling from inside Israel continues. 11. Israeli jets are firing on the headquarters of the Republican Guard. 12. IDF confirms that Israel is launching an attack on targets associated with the Iranian Revolutionary Guard in Syria. Meanwhile, the power has been cut in parts of Damascus.

So it is unclear who started the 'fight' but for now rocket exchanges continue.

But you can watch local coverage of the conflict here.

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Update V: IDF confirms that Israeli air forces have launched an attack on targets associated with the Iranian Revolutionary Guard. Meanwhile, electricity has been cut in parts of Damascus.

My team just captured this video from Mezzeh in Damascus pic.twitter.com/cFJ4tUllXm — Leith Aboufadel (@leithfadel) May 10, 2018

Update IV: Israeli air forces are conducting raids on Republican Guard headquarters and the Mezzah miitary air base.

Update III: AP reports the two sides' versions of events...

Israel:

Iranian forces based in Syria fired 20 rockets at Israeli front-line military positions in the Golan Heights early Thursday, the Israeli military said, triggering an Israeli reprisal and further escalating heightened tensions between the two bitter enemies in neighboring Syria. The Israeli military said its Iron Dome rocket defense system intercepted some of the incoming projectiles, while others caused only minimal damage. There were no Israeli casualties. Lt. Col. Jonathan Conricus, a military spokesman, said Iran's Al Quds force had fired the rockets at several Israeli bases, though he would not say how Israel had determined the Iranian involvement. The incoming attack set off air raid sirens in the Israeli-controlled Golan. Israel "views this Iranian attack very severely," Conricus told reporters. He said Israel had responded, but did not provide details. "This event is not over," he added.

And "Not"-Israel...

Syria's state news agency said early Thursday that Syrian air defenses had intercepted "hostile Israeli missiles," and Syrian media later said the missiles were fired over southwestern Damascus. Pro-Syrian government media and activists said late Wednesday that missiles had been fired toward Israel from southern Syria targeting Israeli positions in the occupied Golan heights. Before that report, Syria state news agency said rockets suspected to have been fired from Israel hit southern Syria's Quneitra province. Activists said it was artillery fire from Israeli positions in the Golan Heights. There were no reports of casualties.

You decide who's telling the truth.

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Update II: Israel has reportedly launched a cruise missile at Damascus...

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Update I: But here's a preliminary timeline of events over the last 24 hours shared by independent journalist Danny Makki on Twitter.

Looks like this fighting could continue well into the night #Iran #Israel #Syria — Danny Makki (@Dannymakkisyria) May 9, 2018

1. Trump withdraws from Iran Nuclear Deal

2. Israel Instantly activates bomb Shelters in Golan Heights

3. Israel reports unusual Iranian activity in Syria border areas

4. Sources/Reports begin discussing imminent threat of Iranian led attacks on Israel from Syria

5. Israel strikes Al-Kisweh industrial area around Damascus with two rockets

6. Syrian State Media claims two further rockets were downed

7. Reports that Eight Iranians among 15 foreign pro-government fighters were killed in the attack which took place yesterday

8. Israel continues a steady build up of troops/tanks on Syrian border this morning

9. Heavy Israeli air activity over the Golan Heights today

10. Israeli rocket flies over Qunaitra going towards Damascus, Syrian air defense fired at it

11. Reports claim that the rocket was downed South East of Damascus, Israeli Jets still heavily present in the skies

12. Numerous artillery and mortar strikes from Israel targeted areas around Al-Baath City in Qunaitra province

13. Israeli Tanks firing at Syrian positions also, no reports of casualties so far

14. Sirens reportedly heard on Israeli side of border

15. Numerous Israeli strikes now reported in Hadar in Qunaitra

16. Syrian air defense firing at Israeli rockets targeting Hadar in Qunaitra.

17. Al- Mayadeen reporting numerous Syrian army strikes (Mortars, Artillery) on Israeli positions near border with Syria. Most of the Syrian missiles fired at #Israel were reportedly intercepted by the Iron Dome

18. Pro Gov Al-Mayadeen stating that 4 Israeli locations have been targeted

19. Reports of more Israeli strikes on Hadar in Qunaitra

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Israel is retaliating against what it has described as an attack by Iranian forces out of Syria on its forward defensive line in the border region of the Golan Heights. The attack began around midnight Wednesday.

Both Israeli and Syrian media have reported shelling and explosions in their territory.

3 sources, one near Khan Arnabeh, 2 in Jubatha al-Khashab, are confirming reports of an Israeli strike on a regime position the western outskirts of Hader, a Druze village that houses Hezbollah-affiliated fighters.

Another Quneitra source confirms the interception by Iron Dome. — Elizabeth Tsurkov (@Elizrael) May 9, 2018

According to al-Mayadeen Syrian forces shelled 10 positions of the Israeli Army with rockets, and several vehicles were targeted with guided missiles.

WOW! Pro gov Mayadeen TV reporting from a military source than any further Israeli attacks will be met with larger attacks on #Israel itself pic.twitter.com/s4KppguqGG — Danny Makki (@Dannymakkisyria) May 9, 2018

If accurate, the strike on Israel by Syrian (and, as Israel alleges, Iranian) forces would mark the first time that the Syrian Army has retaliated against Israel for strikes in Syrian territory, and the first time they've fired directly on Israeli troops, according to WaPo.

Israelis living near the border are now telling the Jerusalem Post that a "prolonged attack" is underway as the two sides exchange fire...

Locals are reporting of an extraordinarily prolonged exchange as #Israel fires back on #Syria positions right now. #Iran — Michael Wilner (@mawilner) May 9, 2018

...And SANA, the Syrian state television station, is reporting shelling in Southwest Damascus, while Syrian air forces are contending with Israeli missiles. There have also been reports that Israel is targeting the Syrian Army 10th Brigade in Qatna in the Damascus countryside.

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An IDF spokesperson has confirmed that Israel sees this as an attack by Iran and are responding accordingly. About 20 missiles were fired by the Iranian Qods Force at Israel's forward defensive line in the Golan Heights, the spokesman said, confirming that Israel's iron dome had intercepted "several" of the missiles. No injuries have been reported so far on the Israeli side.

According to local media reports, several shells have reportedly hit the Syrian governate of Quneitra. The shells were reportedly launched from the Israeli-occupied portion of the Golan Heights. Air raid sirens went off in the Israeli-controlled area shortly after the reported strike.

Meanwhile, the Associated Press reports that the Israeli army says air raid sirens have sounded in the Golan Heights shortly after the Syrian state news agency published reports of rocket fire from Israel into southern Syrian just before midnight local time on Wednesday.

Photos and videos of shells being launched into Israel from Syria have begun appearing on social media.

Explosions heard in the Golan but no reports of rockets landing on the Israeli side. Could be Iron Dome interceptions. https://t.co/AAVOAiGtf8 — Anshel Pfeffer (@AnshelPfeffer) May 9, 2018

מג'דל שמס: כך נשמעו לפני זמן קצר האזעקות ביישוב @alonbd pic.twitter.com/0IbkErlBFO — חדשות עשר (@news10) May 9, 2018

The IDF confirmed that sirens were heard in Golan Heights and that it is "looking into the issue".

Initial report: A short while ago, sirens sounded in the Golan Regional Council in northern Israel — IDF (@IDFSpokesperson) May 9, 2018

Several sirens sounded in the area of the Golan Heights. The details are being looked into and will be given shortly — IDF (@IDFSpokesperson) May 9, 2018

Israel says it is responding to what it describes as an "Iranian attack". Though it's still unclear who fired first.

#Pt. Several artillery strikes between Hader & #Israel|i fence (infiltration attempt?). Sources report Regime artillery is retaliating (#Golan). pic.twitter.com/QisBmsBt3f — Qalaat Al Mudiq (@QalaatAlMudiq) May 9, 2018

An editor at the Jerusalem Post said Israel considers the attack a "severe" event and is preparing a response.

#Breaking: “Prepare for several scenarios.” #Israel says forces of #Iran in #Syria fired roughly 20 projectiles to the #GolanHeights, and consider it a “severe” event requiring a response. — Michael Wilner (@mawilner) May 9, 2018

The IDF has been on high alert in recent days, fearing an attack from Syria. Israel is believed to have carried out a series of deadly airstrikes on Iranian targets in Syria in recent weeks that have killed upwards of ten Iranians.

Meanwhile, as shells are exchanged between Syria and Israel, Israeli Prime Minister Benjamin Netanyahu is in Moscow visiting with Russian President Vladimir Putin.

After 10 hours together, Netanyahu said he conveyed Israel's obligation to defend itself against Iranian aggression. "I think that matters were presented in a direct and forthright manner, and this is important. These matters are very important to Israel's security at all times and especially at this time," he said.