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DAMASCUS, July 19 (Reuters) - Syria's Islamist-led government struggled to implement a ceasefire in the Druze-majority Sweida region on Saturday, amid the sound of machine guns and mortar fire after days of bloodshed.

Reuters correspondents heard gunfire from inside the city of Sweida and saw shells falling on nearby villages. There were no confirmed reports of casualties.

The government previously said its security forces were deployed in Sweida and urged all parties to respect the ceasefire following violence in the area that left hundreds dead.

In a separate speech, Syrian interim President Ahmed al-Sharaa asserted that "American and Arab mediation" had contributed to achieving calm, and criticized Israel for launching airstrikes on Syrian government forces and Damascus in recent days.

* Violence in the Druze region is a challenge to Damascus

The violence around Sweida represents the latest challenge to the control of the Islamist-dominated government in Damascus, which came to power after opposition fighters ousted President Bashar al-Assad in December.

The violence included clashes between the Druze, a religious minority living in southern Syria, the Israeli-occupied Golan Heights, and parts of Lebanon and Jordan, and Syrian Bedouin tribes. This led to clashes between government forces and Druze militants, as well as attacks by government forces on the Druze community.

Israel, which borders Syria, carried out airstrikes on southern Syria and on the Defense Ministry headquarters in Damascus. Israel says it is protecting the Druze minority, of which there is a large population in Israel.

But Israel's position differs from Washington's. The United States supports the central government in Syria under the leadership of the Sharaa government, which has pledged to govern for all citizens. Israel, however , says the government is controlled by jihadists and poses a threat to minorities.

In March, the Syrian army participated in mass killings of members of the Alawite minority, to which most of Assad's elite belong. It clashed with Druze militants in May.

The Sweida Governorate witnessed violence that began with clashes between Bedouin fighters and Druze factions, before Damascus sent government security forces to intervene.

The Syrian presidency announced in a statement issued today "a comprehensive and immediate ceasefire," calling on "all parties, without exception, to fully adhere to this resolution and immediately cease all hostilities in all areas."

The Ministry of Interior said that internal security forces have begun deploying in Sweida.

Al-Sharaa called for calm and said that Syria would not be "a testing ground for projects of partition, secession, or sectarian incitement."

"The Israeli intervention has pushed the country into a dangerous phase that threatens its stability as a result of the blatant bombing of the south and government institutions in Damascus," he added in a televised speech.

Israeli Foreign Minister Gideon Sa'ar criticized Shara'a's statement, describing it as biased toward the perpetrators.

"In Syria (under Shara's leadership), it is very dangerous to be a member of a minority—Kurdish, Druze, Alawite, or Christian," he wrote on his X website. "This has been proven repeatedly over the past six months."

* Sweida hospital is filled with injured people

Mansour Namour, a resident of a village near the city of Sweida, said mortar shells continued to fall near his house this afternoon, and at least 22 people were wounded.

A doctor in Sweida said the shelling has stopped, but the local hospital is full of corpses and wounded.

"The hospital is full of corpses and wounded people, most of them with chest injuries... and limb injuries from shrapnel," said Omar Obeid, head of the Sweida Doctors Syndicate and director of the National Hospital.

US envoy Tom Peric announced on Friday that Syria and Israel had agreed to a ceasefire .

Peric, the US ambassador to Türkiye and Washington's envoy to Syria, called on the Druze, Bedouins, and Sunnis "to lay down their arms and build a new, unified Syrian identity with other minorities."

Israel has attacked Syrian military installations and weapons depots in the seven months since the ouster of President Bashar al-Assad, and says it wants to keep areas of southern Syria near its border demilitarized.

An Israeli official said yesterday that Israel had agreed to allow Syrian forces to enter the Sweida region on a limited basis over the next two days.

(Press coverage by Maya Al-Jubaili, Laila Bassam, Mona Alaa El-Din, and Mohamed Al-Jabali - Prepared by Duaa Mohamed and Mohamed Aysem for the Arabic bulletin - Edited by Hassan Ammar)