Israeli warplanes struck Syria Wednesday, hitting Iranian targets and killing 10 Syrian and foreign fighters in what the Israeli army called a retaliatory attack after explosive devices were found near one of its bases on the occupied Golan Heights.

The airstrikes came hours before US Secretary of State Mike Pompeo was to land in Israel for talks including on Iran, in what was likely to be his last visit to the staunch American ally before President Donald Trump leaves office.

An Israeli army statement said its fighter jets had overnight hit "military targets belonging to the Iranian Quds Force and the Syrian armed forces". The elite Quds Force is the main foreign operations arm of Iran's Revolutionary Guards. 

The targets included "storage facilities, headquarters and military compounds" as well as "Syrian surface-to-air missile batteries," it said.

Syrian state news agency SANA said the strikes had killed three of its soldiers and wounded another.

The monitoring group Syrian Observatory for Human Rights said 10 people were killed, including foreign fighters as well as Syrian soldiers.

The foreigners included five fighters who were "likely Iranian and belonging to the Quds force" as well as two pro-Iran fighters of undetermined nationality, the Britain-based monitor said.

Israel has carried out hundreds of air and missile strikes on Syria since civil war broke out there in 2011, targeting Iranian and Lebanese Hezbollah forces as well as government troops.

- Retaliatory strikes -

The Jewish state rarely acknowledges individual strikes, but has done so when responding to what it describes as aggression inside Israeli territory.

Israel's military said it had discovered improvised explosive devices (IEDs) on its side of the armistice line on the Golan Heights on Tuesday.

"We are talking about three connected Claymore anti-personnel charges that were planted close to an IDF position," army spokesman Jonathan Conricus told reporters Wednesday.

"This was another attempt led by Iranian Quds forces. The actual planting of the IEDs was by Syrian locals but the guidance, instruction and control was by Iranian Quds forces," he said.

Most Arab residents of the Israeli-occupied Golan Heights retain Syrian citizenship, having spurned the offer of Israeli papers.

Conricus said Israel had carried out retaliatory strikes against eight separate targets inside Syria, from the armistice line on the Golan all the way to the southern outskirts of the capital Damascus.

He said they included three Iranian command centres -- a headquarters in the Damascus airport, a Quds Force base in the headquarters of Syria's seventh army division and a "secret military site which served as a hosting facility for senior Iranian delegations".

"We hope now that the message is clear -- that it is unacceptable that the Syrian regime allows and tolerates and facilitates the use by Iranian forces of Syria as a launchpad for attacks against Israel."

Israel and Syria, still technically at war, have a border along the Golan Heights, which the Jewish State has occupied since the Six-Day War of 1967.

Iran has been a key ally of Syrian President Bashar al-Assad's regime throughout the civil war that erupted after the brutal repression of anti-government protests and has killed more than 380,000 people.

- Pompeo visit -

The air strikes came hours before Pompeo was to land in Israel, for talks on Iran that are likely to focus on Israeli fears of a softer policy towards Iran after the Trump administration hands over to Democrat Joe Biden in January.

Israel Prime Minister Benjamin Netanyahu, who called Trump his country's strongest-ever ally in the White House, has heaped praised on the administration for its hardline approach towards Iran.

Trump's so-called "maximum pressure" campaign against the Islamic Republic has included sanctions and scrapping of the nuclear deal agreed between Tehran and world powers during Barack Obama's presidency.

Israeli experts have said Netanyahu is concerned that the president-elect, Obama's former vice president, will seek to re-engage Iran diplomatically, possibly by restoring the 2015 nuclear deal Trump pulled the US out of. 

Bahraini Foreign Minister Abdellatif al-Zayani was also due in Israel for the first visit by a senior official official of the Gulf Arab state since it signed a normalisation deal with Israel on September 15.

The deal was condemned as a betrayal by Iran and its regional allies.