BEIRUT -- Turkish artillery fired shells into Syria for the fourth day in a row on Saturday, retaliating for mortars that landed on Turkish soil. Rebels clashed with Syrian government troops near the border amid renewed fears that the Syrian crisis could spiral into a regional conflict.

Also Saturday, Syrian Defense Minister Gen. Fahd Jassem al-Freij said the rebellion against President Bashar Assad's regime will be crushed and that the violence that has engulfed the country will soon end.

The latest shelling comes a day after Turkish Prime Minister Recep Tayyip Erdogan cautioned Damascus not to test Turkey's "limits and determination" and insisted that his country "was not bluffing" with its warnings.

The crisis began on Wednesday, when a Syrian shell killed five civilians in a Turkish border town and triggered unprecedented artillery strikes by Turkey, coupled with warnings that Turkey would no longer tolerate such acts. Ankara has deployed more troops to its southern border with Syria, and has responded to each shell that has struck Turkish soil with its own artillery barrage.

On Saturday, two mortar shells landed in rural areas near the Turkish village of Guvecci, prompting Turkish return fire, Turkey's media reported. The first exchange happened shortly after intense fighting broke out across the border in Syria's Idlib province between Syrian rebels and regime forces, the private Dogan news agency reported. There were no reported casualties.

A Turkish army unit based near Guvecci promptly responded, firing four 81mm mortars in the first instance and two shells in the second, it said.

The governor's office indicated that the Syrian mortar had landed in Turkey accidentally, saying it was believed "to be have been fired by the forces of the Syrian Arab Republic at Syrian rebel groups on the Syrian side of the border."

The Britain-based Syrian Observatory for Human Rights said rebels had attacked army positions in the Syrian villages of Khirbet al-Jouz and Darkoush about 16 kilometers (10 miles) from Guvecci. Observatory director Rami Abdul-Rahman said both sides were exchanging mortar fire.

The Observatory added that rebels later took over Khirbet el-Jouz and were advancing toward army positions in nearby areas. It said dozens of soldiers were either killed or wounded while three rebels died in the fighting.

Relations between Turkey and Syria, once strong allies, deteriorated sharply after the uprising against Assad began in March last year. Turkey became one of the harshest critics of Assad's crackdown while Syria accused Ankara of aiding rebels.

Turkish Foreign Minister Ahmet Davutoglu told Turkey's state television TRT that "from now on whenever there is an attack on Turkey, it will be silenced."

Also Saturday, Assad made a rare public appearance when he laid a wreath at the country's Unknown Soldier statue in Damascus to mark the 1973 war with Israel, also known in Syria as the October War. Syrian state television broadcast the ceremony.

Syrian state media likened the current crisis to the war with Israel. Damascus denies it is facing a popular uprising, instead blaming the violence on a foreign conspiracy linked to its support for anti-Israeli groups such as Lebanon's Hezbollah.

"There are few differences between the current aggression and the circumstances during the October War, as Syria is facing an enemy armed with Western and Israeli weapons aiming at destroying the Syrian state and punishing its people for foiling all the hegemonic and hostile schemes planned for the region," the official news agency SANA commented.

In comments marking the anniversary of the 1973 Arab-Israeli war, Syria's defense minister said the government is ready to give amnesty to rebels who repent and that those who don't "will be crushed under the feet of our soldiers."

Al-Freij, who became defense minister in July after his predecessor was assassinated, also said Syria's "armed forces are intent to bring back security and stability to our beloved Syria."

"The most dangerous parts of the conspiracy have been passed and the killing is on its way to decline," he said.

Al-Freij, who rarely makes public statements, spoke as Syrian troops launched a major offensive to retake rebel-held areas in the northern city of Aleppo, the central city of Homs and towns near the border with Lebanon.

Despite his claims of government troops being on the brink of restoring stability, the violence across the country shows no signs of abating. Activists say that at least 30,000 people have been killed since the anti-Assad uprising began in March 2011.

Lebanese security officials meanwhile said Syrian troops backed by warplanes and helicopter gunships began a major attack against rebel-held areas near the Syrian town of Quseir adjoining Lebanon's Bekaa Valley. The Lebanese-Syrian border has also been the site of deadly border incidents.

The officials, who spoke on condition of anonymity in line with regulations, said no shells fell on the Lebanese side of the frontier Saturday. They added that Lebanese troops were put on high alert in the border area to make sure the fighting does not reach Lebanon.

The Observatory and the Local Coordination Committees, another activist group, reported intense shelling in rebel-held areas of Aleppo and Homs. They said the government shelling of the town of Taibeh near Homs killed at least 10 people and wounded dozens.

A Syrian official said government troops on Saturday captured the strategic Sakhour roundabout in Aleppo after days of heavy fighting. The official spoke on condition of anonymity because he was not authorized to speak to the media.

The fight for Aleppo, a city of 3 million that was once a bastion of support for Assad, is critical for both the regime and the opposition. Its fall would give the opposition a major strategic victory and control of a stronghold in the north near the Turkish border. A rebel defeat, at the very least, would buy Assad more time.