Ankara (AFP) - Almost 600 Turkish troops pushed deep into Syria in an unprecedented incursion Sunday, relocating a historic tomb and evacuating the soldiers guarding the monument after it was surrounded by Islamic State (IS) jihadists.

The Damascus government, which no longer controls the area in Aleppo province but is at loggerheads with Ankara over the Syria conflict, lashed out at what it described as a "flagrant aggression" on Syrian territory.

Turkish Prime Minister Ahmet Davutoglu said the mission had succeeded, with the soldiers returning safely home and also salvaging the tomb containing the remains of Suleyman Shah, grandfather of the Ottoman empire's founder, Osman I.

A Turkish government official confirmed to AFP that the mission was the first incursion Turkish troops had launched inside Syria since the civil war began in 2011.

Turkish tanks had driven through the ruined streets of the Syrian town of Kobane -- controlled by Kurdish fighters after a months long battle with jihadists -- on their way to the tomb at the start of Operation Shah Firat (Shah Euphrates) late on Saturday.

In a hugely symbolic move, the troops also seized control of a new area of raised ground inside Syria easily visible from the Turkish border to rebury the remains of Suleyman Shah and raised the Turkish flag over the area.

Images taken from the border indicated that the remains of Suleyman Shah had been reburied in their new location on the top of a mound during the day in the Syrian district of Eshme, just 200 metres (650 feet) from the Turkish border.

There were reportedly 40 Turkish soldiers guarding the mausoleum complex of Suleyman Shah on the Euphrates River, which under a 1920s treaty is considered sovereign Turkish territory and carries huge symbolic importance to Turks as a link to their pre-Ottoman past.

After taking everything of historical value, the Turkish troops detonated the building that housed the tomb so it was not misused afterwards by jihadists, Turkish media said.

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- 'Keep the memory alive' -

A soldier was killed in an accident during the operation to evacuate the guards at the tomb, which is some 37 kilometres (23 miles) inside Syrian territory, the Turkish army said in a separate statement.

It said the soldier lost his life in the "initial stage" of the operation but emphasised there were no clashes during the mission.

Davutoglu said the operation had posed "considerable potential risks" but in the end Turkey had left nothing behind.

"It was a highly successful operation to the last degree," he said after watching the operation in real time from Ankara along with military chiefs.

He said that 572 Turkish soldiers using 39 tanks, 57 armoured vehicles and 100 other military vehicles took part in the operation.

The government official said that warning shots had been fired to prevent any danger from IS.

Denouncing he incursion, the Syrian foreign ministry said it had been informed by Ankara but Turkey had not waited for their consent.

The tomb of Suleyman Shah, who is said to have died in 1236, is considered Turkish territory under the 1921 Treaty of Ankara between the Turkish authorities and France, which then controlled French-mandated Syria.

Erdogan said: "Our flag will continue to fly in a new place to keep alive the memory of our ancestors."

The figure of Suleyman Shah helps Turks link the Ottoman dynasty, which according to tradition was founded by Osman in 1299, with the early Turkic tribes who swept through Anatolia from Asia.

"A nation cannot build a future without a past and symbols of the past," said Davutoglu.

- 'Not a military victory' -

Davutoglu and Erdogan said the transfer of the tomb to a new location inside Syria was fully within international law as it did not violate the 1921 treaty.

This is not the first time the tomb has been relocated -- it was moved in the 1970s when its then location, also on the Euphrates, was flooded by the Syrian authorities to construct the Tabqa Dam that forms Lake Assad.

The tomb had for years been watched over largely by conscripts but in March 2014 Turkey reportedly sent several dozen special forces to guard it.

Erdogan and Syrian President Bashar al-Assad were formerly close allies but fell out when Damascus began suppressing an uprising in 2011. Ankara now believes ousting the Syrian president is a key condition for ending Syria's civil war.

The operation to evacuate the soldiers guarding the tomb took place as Turkey comes under pressure from its Western allies to play a greater role in the fight against IS jihadists.

The United States and Turkey on Thursday signed a deal to train and equip thousands of moderate Syrian rebel forces opposing Assad after several weeks of talks.

Turkey's opposition angrily lashed out at the government, accusing it of dressing up a military withdrawal as a victory.

"For the first time in the history of the Turkish Republic, we are losing territory without fighting for it," said Gursel Tekin of the opposition Republican People's Party (CHP).