Turkey’s military fired 40 shells at ISIS and U.S.-backed Kurdish forces across the Syrian border on Tuesday.

The projectiles were launched in response to a prior assault Turkey had suffered with two mortar shells which were launched from Syria territory.

South-eastern Turkish border towns of Karkamis and Kilis, were hit by the mortars, Turkish broadcaster NTV reported.

No casualties were accounted for by the two mortar rounds fired at the Turkish towns, however, a garden outside a mosque in Karkamis was reportedly damaged.

Clashes in northern Syria between ISIS and Syrian opposition fighters, had led to the mortar attack, according to Turkish state-run Anadolu Agency.

Turkey’s military on Monday launched howitzer attacks on ISIS while firing artillery on Kurdish YPG militants in Syria. YPG are considered a terrorist organization in Turkey.

According to a senior Syrian opposition official, Turkish-backed Syrian opposition fighters are preparing for an offensive to seize control of the Syrian city Jarablus.

ISIS-controlled Manbij city was liberated earlier this month by the Kurdish-led Syria Democratic Forces. This sparked concerns among Turkish officials that Kurdish militants would seize control of the entire border strip with Turkey.

The head of Syrian Observatory for Human Rights, Rami Abdul Rahman, said the Turkish attacks in Syria aimed to hinder the advancement of Kurdish-backed troops towards Jarablus. This would hinder any possible Kurdish plans to expand in the area.

The city of Jarablus is a vital supply line and the last border point that connects ISIS directly to Turkey. It also separates areas north of Syria controlled by the Kurdish.

A writer for the Hurriyet newspaper, Abdulkadir Selvi, said Turkey’s offensive in Jarablus could start soon at any time.

The offensive has not been confirmed by the Turkish authorities.

The counter-strikes came a day after Turkey’s Foreign Minister Mevlut Cavusoglu pledged to “wipe out” militant groups such as ISIS and YPG from Turkey after the suicide bombing of a wedding in Gazientep on Saturday which left about 54 people dead and over 60 people injured.

“Traitors should know this: FETO, PKK, PYD, YPG, also known as ISIS, we will cleanse them all from our country and wipe out all of them,” said Cavusoglu.

“Members of FETO had tanks and helicopters on the night of the coup attempt. They were bombing and shooting at our people with sharpshooters from the high hills,” he recalled.

U.S. Vice President Joe Biden is set to travel to Ankara on Wednesday for talks.