Since the beginning of the fasting month of Ramadan on August 1, Assad's forces have mounted operations across the country to try to suppress protests demanding political freedom and an end to 41 years of Assad family rule.
"I can see the silhouettes of two grey vessels. They are firing their guns and the impact is landing on al-Raml al-Filistini and al-Shaab neighborhoods," one witness told Reuters by phone from Latakia
, where tanks and armored vehicles were deployed three months ago to crush dissent against Assad in mainly Sunni neighborhoods of the mixed city.
"This is the most intense attack on Latakia since the uprising. Anyone who sticks his head out of the window risks being shot. They want to finish off the demonstrations for good," he said.
Around 20,000 people have been rallying daily to demand Assad's removal in different areas of the city after Ramadan evening prayers, said the witness, a university student who did not want to be further identified.
n National Organization for Human Rights, headed by dissident Ammar al-Qurabi, said it had the names of 26 civilians killed in Latakia, including a two-year-old girl, Ola al-Jablawi. The deaths came after security forces shot dead 20 people during nationwide marches on Friday.
Assad comes from Qerdaha, a village in the Alawite Mountains 28 km (17 miles) southeast of Latakia, where his father, the late President Hafez al-Assad, is buried.
The Syrian Observatory for Human Rights said most of the casualties were shot by machineguns.
"After heavy firing, troops and shabbiha (militiamen loyal to Assad) have reached the main square in al-Raml al-Filistini, where the crowds have been demonstrating peacefully for freedom and the downfall of the regime," said a statement by the opposition group.
The Syrian Revolution Coordinating Union said four more civilians were killed elsewhere in Syria on Sunday.
The official state news agency denied that Latakia was shelled from the sea and said two police and four unidentified armed men were killed when "order preservation forces pursued armed men who were terrorizing residents.. and using machineguns and explosives from rooftops and from behind barricades."
The assaults by Syrian security forces are being met with increasing international condemnation. United Nations deputy political affairs chief Oscar Fernandez-Taranco was quoted by diplomats in New York on Wednesday as saying Assad's forces had killed nearly 2,000 Syrian civilians since March -- 188 since July 31 and 87 on August 8 alone.
The 57-member Organization of Islamic Cooperation called on Saturday for an immediate halt to the military campaign against protesters. U.S. President Barack Obama and Saudi Arabia's King Abdullah repeated their calls for the military assaults to stop.
Obama spoke to British Prime Minister David Cameron and the leaders called for an immediate end to attacks by Assad's forces, the White House said.
It said Obama and Cameron would "consult on further steps in the days ahead." Washington wants Europe and China to consider sanctions on Syria's oil industry, a key source of hard currency for the government.
Syrian authorities have expelled most independent media since the beginning of the uprising, making verifying reports from inside the country difficult.
Residents and rights campaigners said security forces and shabbiha continued house-to-house raids on Sunday in the northwestern Idlib province on the border with Turkey, the southern Hauran Plain, the Damascus suburbs and around the city of Hama, which remains besieged by the military.
Hundreds were arrested, adding to at least 12,000 who have been detained since the uprising and thousands of people already held as political prisoners before it, they added.
Assad, from Syria's Alawite minority, has repeatedly said Syria is facing a foreign conspiracy to divide the country of 20 million. The authorities blame "armed terrorist groups" for the bloodshed, and say 500 police and troops have been killed.
Assad's statements find little support among the majority Sunni population of Latakia, where, as in other towns and cities, the ruling minority has encouraged Alawites to move from their traditional mountain regions, offering them cheap land and jobs in the public sector and security apparatus.
Latakia port figures highly in the Assad family domination of the economy, with Bashar al-Assad
's late uncle Jamil having been in virtual control of the facility, and a new generation of family members and their friends taking over.
Demonstrations against Assad during the five-month uprising have been biggest in Sunni neighborhoods of Latakia, including Salibiya in the center of the city and Raml al-Filistini and al-Shaab on the southern shore.
Troops have been besieging the neighborhoods for months, residents say, with garbage going uncollected and electricity often cut.