BEIRUT (AP) -- A besieged Syrian city came under fresh artillery fire early Monday as a deadly military assault left President Bashar Assad's regime increasingly isolated, with Arab nations forcefully joining the international chorus of condemnation for the first time.
The renewed violence in the eastern city of Deir el-Zour comes a day after at least 42 people were killed there in an intensifying government crackdown on protesters.
"We heard very loud explosions, and now there's intermittent gunfire," an activist said in the city said, speaking on condition of anonymity for fear of reprisals. He said people were too terrified to take the wounded to government hospitals, instead treating them at home or in makeshift hospitals.
The Local Coordinating Committees, which help organize the protests and track the uprising, said machine fire and artillery blasts resumed early Monday in Deir el-Zour. Syrian troops also stormed Maaret al-Numan in the northern province of Idlib at dawn, activists said.
"Forces entered the city from its eastern side and they are preventing the residents from entering or leaving the city," the LCC said in a statement.
More than 300 people have died in the past week, the bloodiest in the five-month uprising against Assad's authoritarian rule. Deir el-Zour, in particular, has come under withering attack. The city is in an oil-rich but largely impoverished region of Syria known for its well-armed clans and tribes whose ties extend across eastern Syrian and into Iraq.
Also Monday, the Internet hacking group known as Anonymous claimed credit for vandalizing the Syrian military's website. The site quickly became unavailable, but screenshots circulated online showed the group's trademark headless suit and a message addressed to the Syrian people saying that "the world stands with you against the brutal regime."
The government's crackdown on mostly peaceful, unarmed protesters demanding political reforms and an end to the Assad family's 40-year rule has left more than 1,700 dead since March, according to activists and human rights groups. Assad's regime disputes the toll and blames a foreign conspiracy for the unrest, which at times has brought hundreds of thousands of protesters into the streets.
The international community has sharply condemned the government's crackdown, imposing sanctions and demanding an immediate end to the attacks. France and Germany renewed their condemnation Monday.
But in a sign of growing outrage, Syria's Arab neighbors joined that chorus of criticism, voicing their concerns of a crackdown that intensified on the eve of the holy month of Ramadan -- a time of introspection and piety characterized by a dawn-to-dusk fast.
Muslims typically gather in mosques during the month for special nightly prayers after breaking the fast, and the Assad government has been trying to prevent such large gatherings from turning into more anti-government protests.
After sunset Sunday, thousands of people poured into the streets in areas around Syria, including the capital Damascus and its suburbs, the village of Dael in the south, the central city of Homs, Latakia on the Mediterranean coast and northern city of Aleppo, according to the Local Coordination Committees. There were reports of shootings but no immediate word on casualties, according to the LCC.
Saudi Arabia's king -- whose country does not tolerate dissent and lent its military troops to repress anti-government protests in neighboring Bahrain -- harshly criticized the Syrian government. King Abdullah said Sunday he was recalling his ambassador in Damascus for consultations, and demanded "an end to the killing machine and bloodshed."
"Any sane Arab, Muslim or anyone else knows that this has nothing to do with religion, or ethics or morals; spilling the blood of the innocent for any reasons or pretext leads to no path to ... hope," the king said in a statement.
Abdullah accused the Syrian government of a disproportionate response, and said it must enact speedy and comprehensive reforms to avoid a future of chaos.
The 22-member Arab League, which had been silent since the uprising began, said Sunday it is "alarmed" by the situation in Syria and called for the immediate halt of all violence. The prime minister of Syria's key trade partner and neighbor, Turkey, said he was dispatching his foreign minister to Damascus on Tuesday to deliver a strong message about the crackdown.
In a front-page article Monday, Syria's pro-government Al-Watan newspaper said the Saudi and Arab League statements ignore the "extremist and terrorist groups that have sought to tear up Syria's unity."
Syria's smaller neighbor, Jordan, urged dialogue, but stopped short of condemning Damascus. Jordanian Foreign Minister Nasser Judeh was quoted on Monday by the country's official Petra News Agency as saying the violence was "disturbing." But he also said Amman does not interfere in its neighbor's internal affairs.
German Chancellor Angela Merkel's spokesman Christoph Steegmans warned that "if Assad should continue to refuse having a dialogue with the people, he no longer has the legitimization to lead his country."
France's Foreign Ministry said: "The time of impunity for Syrian authorities is over. Bloody repression on a large scale must stop."
Assad has shrugged off months of criticism and sanctions, blaming armed gangs for the violence while offering reform measures that have failed to placate the protesters demanding sweeping changes.
In Deir el-Zour, which sits about 280 miles (450 kilometers) east of the capital Damascus, troops stepped up a siege that had already been going on for days. A pre-dawn raid on the city killed at least 42 people Sunday, said Abdul-Karim Rihawi, the Damascus-based chief of the Syrian Human Rights League, and Ammar Qurabi, who heads the National Organization for Human Rights in Syria.
An activist in the city told The Associated Press that the military attacked from four sides and took control of eight neighborhoods.