ANKARA, Turkey (AP) -- Syrian forces on Monday fired across the border at a refugee camp in Turkey, killing one and wounding four, activists said. It is the first such attack since Ankara began allowing thousands of refugees to find shelter in the country.
A Turkish government official, speaking on condition of anonymity in line with government rules, said his country -- which stands at the forefront of calls for the ouster of Syrian President Bashar Assad -- immediately protested the incident and called for fire to be halted.
The Britain-based Syrian Observatory for Human Rights said the incident began at about 4 a.m. Monday when opposition fighters attacked Syrian forces at the Salameh border crossing with Syria.
A protracted gunbattle ensued between the rebels and Syrian troops trapped at the crossing, said Rami Abdul-Rahman, a spokesman for the Observatory. Abdul-Rahman said several government soldiers were killed in the ambush.
The fighting spilled over into Turkey when eight wounded opposition fighters escaped to the camp on the Turkish border and Syrian forces kept firing at them, Abdul-Rahman said. The spokesman said five people were injured in the camp in the town of Kilis in the southwestern province of Gaziantep, and that one later died of his injuries.
Gaziantep Gov. Yusuf Odabas said the wounded included three Syrians, one Turkish translator and one Turkish policemen. The translator had entered the camp to try to help calm a protest against the Syrian regime, he said.
Odabas said, meanwhile, that two of 13 Syrians who had been wounded in clashes inside Syria and were brought to Kilis for treatment earlier Monday have died.
The U.N. says more than 9,000 people have been killed in Syria since the anti-Assad revolt began 13 months ago with peaceful protests. The uprising has turned increasingly violent in recent months in the face of a brutal government crackdown.
Under a U.N.-brokered cease-fire deal, Syrian troops were to pull out of population centers by Tuesday morning. However, the Syrian government said Sunday it cannot do so without written guarantees from opposition fighters that they will lay down their arms, effectively scuttling a deal that was to pave the way for talks between the government and the opposition on a political transition.
Naci Koru, Turkey's deputy foreign minister, said the deadline for the withdrawal of has become "void at this stage," state-run TRT television reported.
U.N. envoy Kofi Annan is scheduled to pay a brief visit to one of the refugee camps in Hatay province, bordering Syria, on Tuesday afternoon before heading to Iran, Turkey's Foreign Ministry said. Annan's office confirmed the trip to Turkey.
"Annan's one-hour visit to Hatay tomorrow is critical, he will see the situation himself," the TRT quoted Koru as saying on Monday.
Turkey hosts some 24,000 Syrian refugees, including hundreds of army defectors, and has floated the idea of setting up a buffer zone inside Syria if the flow of displaced people across its border becomes overwhelming. Parts of the southern Turkish region near Syria are informal logistics bases for rebels, who collect food and other supplies in Turkey and deliver them to comrades on smuggling routes.
Separately, a leading international human rights group said Syrian forces have summarily executed more than 100 people, most of them civilians. Human Rights Watch said it has documented the killings of 85 civilians, including women and children, and the summary executions of at least 16 wounded or captured opposition fighters.
In one case, troops stabbed to death four residents of the city of Homs outside their apartment, in front of their relatives, before opening fire on neighbors, killing one and wounding a second, the report said.
"In a desperate attempt to crush the uprising, Syrian forces have executed people in cold blood, civilians and opposition fighters alike," said Ole Solvang, a researcher for the group. "They are doing it in broad daylight and in front of witnesses, evidently not concerned about any accountability for their crimes."
The New York-based group said it only included cases corroborated by witnesses, but has received many more reports of similar incidents.
The group said it documented several cases of mass executions in March in the cities of Homs and Idlib, two centers of the uprising. This includes the killing of 13 people in a mosque in Idlib, the executions of 25 men in a raid of the Sultaniya neighborhood of Homs, and the killing of 47 people, mainly women and children, in three other areas of Homs, the group said.
Two witnesses describing the March 11 killings in Idlib said the Bilal mosque in the city had been used as an initial collection point for those killed and wounded in an army raid. When relatives came to identify the dead, several were led by soldiers out of the mosque, blindfolded and lined up against a wall. More than a dozen soldiers opened fire, killing at least 13 people, the witnesses said.
The Syrian government typically does not comment on such reports.
The allegations came as opposition activists reported that Syrian forces pressed ahead with raids and shelling attacks on the towns of Tel Rifaat in the northwest and Muhassan in the east of the country Monday.
Annan's six-point peace plan has the backing of Syria ally Russia, which is hosting Syrian Foreign Minister Walid Muallem for talks later Monday. Moscow has shielded the Assad regime against international condemnation in the past.
It is not clear whether the Kremlin will try to pressure Syria to comply with the cease-fire plan, though Russia said Monday it may send its observers to Syria as part of a U.N. monitoring mission
The international community, which so far is unwilling to contemplate military intervention, has had little leverage over the Syrian regime.