(CNN) -- At least 16 people have been killed over the last two days in and around the Syrian town of Hama, which a human rights group described Wednesday as the "latest city to fall victim to President Bashar al-Assad's security forces."
Human Rights Watch reported that the crackdown by security forces and pro-government armed groups known as "shabiha" began after a huge peaceful demonstration Friday.
The group, a humanitarian watchdog agency, said the forces "raided homes," opened fire and "set up checkpoints" in and around the restive city, the site of a deadly military clampdown nearly 30 years ago.
"Hama is the latest city to fall victim to President Bashar al-Assad's security forces despite his promises that his government would tolerate peaceful protests," said Sarah Leah Whitson, Middle East director at Human Rights Watch. "Security forces have responded to protests with the brutality that's become familiar over the past several months."
Residents said at least 16 people were killed and dozens more were wounded, Human Rights Watch said. It said the National Organization for Human Rights, a Syrian group, reported 22 deaths.
Rami Abdulrahman of the Syrian Observatory for Human Rights said 14 people were killed and 40 people were wounded in the reported clashes on Tuesday alone in the Hama area and that electricity and water had been shut off.
"Syria's security forces still believe they can shoot their own people into submission," Whitson said. "But their bloody tactics only serve to deepen the gap between citizens and the institutions that are supposed to protect them."
Syria has denied that a military campaign was under way against Hama, even as human rights groups reported deaths, arrests and clashes on the outskirts of the city.
"The Syrian army did not enter and will not enter Hama," a Syrian government official told CNN Wednesday. "The army is present at the city's entrances to facilitate the entry of government employees who live in the Hama countryside and work in government offices in the city; some people in Hama prevented them from entering the city by cutting off roads."
The official added that the army's presence at the entrances was intended solely to "facilitate" the movement of these people.
On Wednesday, the state-run Syrian Arab News Agency said a law enforcement officer was killed and 13 others were wounded when "armed groups" fired shots at security forces and used Molotov cocktails and nail bombs.
"Saboteurs cut off roads, set up roadblocks and burned tires in several areas in the city of Hama on Tuesday, in addition to committing acts of vandalism and burning a bus," the news agency said, citing an official source.
In the ensuing confrontation, one law-enforcement officer was killed and 13 were wounded, the agency reported, while a number of armed men were wounded and others were arrested. There were other acts of vandalism reported on Monday, and the source told SANA "citizens asked law-enforcement sources to intervene and protect them from the armed groups terrorizing them."
Activists have said that, since mid-March, violence has been started by security personnel who have used brute force to break up peaceful demonstrations, but the Syrian regime has blamed "armed groups" for the bloodshed.
The city is a sensitive spot for Syrian authorities. In 1982, it was the scene of a brutal military crackdown targeting Sunni Muslims by the Alawite-dominated government of Hafez al-Assad, President Bashar al-Assad's late father. Many thousands were killed, with Human Rights Watch putting the toll at 10,000.
Human Rights Watch said "security had been largely absent" from the 800,000-population city since June 3, "when they opened fire on anti-government protesters, killing at least 60 people, according to media reports. In the following weeks, Hama residents took to the streets for regular protests that participants and media reports consistently reported as peaceful."
But the dynamics changed after the Friday demonstration in al-Assi square. There were an estimated tens of thousands of protesters and the gathering was called the largest demonstration in the country since the uprising started nearly four months ago.
"The protest was peaceful and unimpeded by government forces, according to witnesses, media reports, and videos reviewed by Human Rights Watch," the group said.
On Saturday, however, al-Assad fired the governor of Hama province and security personnel kicked off their raids and began arresting people, HRW said.
Human rights lawyer Razan Zeitoune told Human Rights Watch that security forces "entered the outskirts of the city" on Saturday and began arresting people. Residents then "set tires on fire to prevent security forces from entering their streets."
"We had a system prepared for when the security forces came to arrest people," one resident reported.
"When we saw them coming, we would bang pots and pans to alert everyone else so the young men in the neighborhood could leave their homes and escape. After a few hours, security forces caught on to the system, so they started throwing tear gas and stun grenades so people would be too scared to leave their homes and run away. Security forces then arrest people in bulk and load them into big cars; we don't know where they're taking them. They're targeting men between 10 and 45 years old."
Security forces set up checkpoints Sunday at city entrances and "deployed in large numbers in the city." Witnesses cited by Human Rights Watch saw security forces in military clothing and men in civilian dress making arrests.
"The forces would surround a building with a big number of cars, then go inside to arrest their targets," one witness told Human Rights Watch. "They also drove tanks through the streets to scare us by reminding us of the 1982 massacre."
Of the two people killed on Monday, one was a 13-year-old boy from a village west of Hama. Human Rights Watch also said 14 residents were fatally shot Tuesday.
Human Rights Watch said the Syrian army surrounded a hospital on Tuesday, "scaring many of those who had assembled around the hospital, but did not enter the facility or arrest any of the wounded there."
Arrests of men and women were reported, and women also were assaulted and beaten, one witness told Human Rights Watch.
CNN's Tracy Doueiry contributed to this report