Turkey's army backed by international coalition air strikes on Wednesday launched an operation involving fighter jets and tanks to drive Islamic State jihadists out of a key Syrian border town.

The air and ground operation, the most ambitious launched by Turkey in the Syria conflict, is aimed at clearing jihadists from the town of Jarabulus, which lies directly opposite the Turkish town of Karkamis, the prime minister's office said.

The operation -- named "Euphrates Shield" -- began around 4:00 am local time (0100 GMT) with Turkish artillery pounding dozens of IS targets around Jarabulus.

Turkish F-16 fighter jets and coalition war planes also hit targets inside Syria while an AFP photographer then saw around a dozen Turkish tanks cross into Syria to support the operation.

Tensions had flared across the Syria-Turkey border the previous day following rocket fire from Jarabulus which landed inside Turkey, with the Turkish army firing howitzer rounds in response.

The operation also appeared aimed at pre-empting any assault on Jarabulus by pro-Kurdish militias, who also oppose IS but are accused by Turkey of seeking to carve out a Kurdish region in northern Syria.

"God willing, we will get a result in a short time" to kick IS out of Jarabulus, Interior Minister Efkan Ala told the state-run Anadolu news agency, saying Turkey was working with coalition partners and moderate Syrian opposition.

Turkish authorities had late Tuesday ordered the evacuation of Karkamis for safety reasons, raising expectations that an offensive was imminent.

- 'Tanks head to border' -

The AFP photographer in Karkamis saw 11 Turkish tanks crossing the frontier and then firing on Jarabulus.

They were followed by several smaller military vehicles believed to be carrying pro-Ankara Syrian rebels who had also crossed over.

Syrian activists have said hundreds of pro-Ankara rebel forces are waiting on the Turkish side of the border to take part in a ground operation to seize Jarabulus from the jihadists.

Air strikes by Turkish jets also echoed through the skies. The effects of one air strike on the northern outskirts Jarabulus were easily visible, sending up a cloud of black smoke and sand.

Turkey will want to show with the operation that it is serious about taking on IS, which has been blamed for a string of attacks inside the country, the latest a weekend attack on a Kurdish wedding in Gaziantep that left 54 dead.

Ankara was long accused of turning a blind eye to the rise of IS in Syria and even aiding its movements to-and-fro across the border, claims the government had always vehemently denied.

The launch of the operation comes as US Vice President Joe Biden arrived in Ankara to meet Turkish President Recep Tayyip Erdogan, with agreeing a unified strategy on Syria set to be a crucial issue.

Biden is likely to face expressions of alarm from Turkey about the activities inside Syria of the People's Protection Units (YPG) militia, which Washington sees as an ally but Ankara regards as a terror group.

Saleh Moslem, the head of the Democratic Union Party (PYD), the YPG's political wing, tweeted that Turkey was now in the "Syrian quagmire" and would be "defeated" like IS.

- Special forces on ground -

The air strikes by Turkish F-16s were the first such assaults since a November crisis with Russia sparked when the Turkish air force downed one of Moscow's warplanes.

A dozen IS targets were completely destroyed in the air strikes. Turkish artillery meanwhile destroyed 70 IS targets, television said.

Security sources quoted by Turkish television said a small contingent of special forces travelled a few kilometres into Syria to secure the area before a possible larger ground operation.

The incursion by Turkish special forces and tanks is the first such into Syria since February 2015, when hundreds of Turkish troops crossed the border to move the relics of the grandfather of the founder of the Ottoman Empire.

The movements have come at a critical juncture for Turkey in Syria's five-and-a-half-year war, with signs growing it is on the verge of a landmark policy shift.

Ankara has always called for the removal of President Bashar al-Assad, putting Turkey at odds with his main supporters Iran and Russia.

However Prime Minister Binali Yildirim acknowledged at the weekend for the first time that Assad was one of the "actors" in Syria and may need to stay on as part of a transition.

Turkey has been shaken by one of the bloodiest years in its modern history, with a string of attacks by IS jihadists and Kurdish militants and the botched July 15 coup.

The attack Saturday on a wedding party for a young couple has horrified the country, with the majority of the 54 victims aged under 18 and including children as young as four.