BEIRUT — Syrian security forces opened fire on anti-government protesters in several towns Friday afternoon, killing dozens of people after crowds took to the streets to call for an end to the rule of President Bashar al-Assad, activists said.

As reports of the violence trickled out of cities and towns throughout the day, a picture began to emerge of a broad crackdown on the protest movement despite ostensible government concessions earlier in the week.

At least 43 people were confirmed killed and many others were injured, according to Wissam Tarif, director of the Syrian human rights organization INSAN. Razan Zaitouneh, a human rights lawyer in Damascus, said 76 people were confirmed dead, more than half of them in the southern town of Izra and the central city of Homs. Zaitouneh listed eight other cities and towns where deaths were reported.

Among the dead were at least eight people who were shot by government forces in the Damascus suburb of Douma, and 19 who were shot in Homs, Zaitouneh said. She said 20 people were killed in Izra, about 20 miles northeast of Daraa where the uprising began last month.

“There was no provocation,” Tarif said of the shooting in Homs, where activists had reported at least two dozen deaths earlier in the week. “There were forces being deployed since last night. When people went out in Homs, the security forces stepped out … and immediately started shooting.”

The state news agency SANA reported that “limited numbers” of demonstrators took to the streets Friday around Syria.

Security forces and police used “hoses and tear gas to settle scuffles that erupted between demonstrators and citizens and to protect private properties,” the agency said, adding that some people were injured.

Thirteen Arab human rights groups signed a statement Friday blasting the Arab League for supporting Syria’s candidacy for a seat on the U.N. Human Rights Council in a vote set for May.

The league’s support “shows flagrant disregard for the feelings and rights of the Syrian people, who have broken the barrier of fear and risen up in revolt,” said the statement, which was signed by Egyptian, Bahraini, Algerian, Saudi, Yemeni, Syrian, Sudanese and Iraqi nongovernmental rights groups.

The groups criticized the Arab League for “double standards,” pointing at its stance against the Libyan government’s crackdowns on protests but accusing the organization of turning a blind eye to rights abuses in Bahrain and Yemen. In Syria, they said, “it seems as if the League of Arab States is rewarding the regime for its repression.”

The protests spread despite tanks and checkpoints stationed across the country to control the demonstrations that have grown into a weekly ritual after Friday Muslim prayers.

In Damascus, the capital, security forces shot into the air near crowds. In the past, security forces had responded to demonstrations there with beatings and tear gas, said Radwan Ziadeh, director of the Damascus Center for Human Rights Studies and a visiting scholar at George Washington University. Police were taking cell phones from protesters to stop them from recording video of the scene, he said.

In Damascus, some of the injured were arrested, and some were brought to hospitals, Tarif said, including the Tishreen Military Hospital, where he said people have disappeared and Red Cross officials and diplomats have been barred from visiting.

A video uploaded to YouTube showed a crowd kicking the fallen head of a statue of Hafez al-Assad, the president’s father. The video was labeled with Friday’s date and the name of the suburb Darayya, about four miles southwest of Damascus, where gunfire also was reported.

“The sound of live shooting, it’s at the main circle at the entrance of Darayya,” said a resident there who did not want to be named for security reasons. He said the shooting began after protesters tried to remove pictures of the president near an entrance to the city. The street outside his home was filled with tear gas, he added.

Witnesses quoted by news agencies said the security forces also clashed with demonstrators in the cities of Baniyas and Daraa, among other places. The accounts could not immediately be confirmed independently because Syria has restricted access to the country by foreign reporters.

Earlier in the day, government tanks and armored vehicles blocked city entry points and roads between towns in an apparent attempt to prevent smaller protests from coalescing and gaining momentum, witnesses said. Last Friday, tens of thousands reportedly marched from Douma, increasing in number as they passed through other suburbs en route to Damascus.

“Douma and Harasta [another Damascus suburb] are under siege by the army,” said a witness in Douma who did not want to be named for security reasons. He said he saw tanks and armored vehicles in his town. “The army and security, they put checkpoints at all entrances of Damascus, not to allow people to enter,” he said by telephone.

Still, protesters planned to try to breach the checkpoints, he said.

Friday, the Muslim day of prayer, has been the traditional day of protest in Syria and other countries involved in a wave of popular uprisings against autocratic regimes in the region.

After prayers, about 2,000 people began gathering in front of the al-Hassan mosque in a commercial area in the heart of Damascus, said Ziadeh.

Protests also erupted in the towns of Amudah, Zabadan and Saraqab, activists said. In Qamishli, a northeastern Kurdish city that has been the seat of earlier protests, 2,500 people shouted, “Azadi, Azadi!” and “Ekiti, Ekiti,” the Kurdish words for freedom and unity, Ziadeh said.

Another activist said the protests in Douma had reached 10,000 and that 7,000 were protesting in Qamishli.

The Friday protests came a day after Assad formally abolished the country’s security court and lifted despised emergency laws that had banned demonstrations for nearly half a century. However, new laws requiring government approval for demonstrations meant that Friday’s protests were illegal.

Syrian Justice Minister Tayseer Qalla Awad said the new laws would have “enormous” benefits and would “reflect President al-Assad’s response to the people’s demands,” the state-run news agency SANA said Friday. Opponents disagreed, calling the laws a new version of the old ones.

The Assad government this week replaced a governor in Homs, the scene of crackdowns earlier this week that left up to two dozen people dead. Assad earlier had replaced his Cabinet and offered citizenship to the country’s Kurdish minority in an attempt to defuse the crisis.

So far, none of his concessions has quieted the protesters, who began in March by calling for reforms but since have escalated their demands to include the president’s ouster.

Assad, 45, took power 11 years ago after the death of his father, who ruled Syria for 29 years. The government, which has close ties to Iran, has been considered one of the most repressive in the Middle East. More than 200 people have been killed in clashes with security forces since the uprising began six weeks ago, human rights groups say.

Although the protests have increased in size and frequency, most Syrians so far have stayed out of them, either out of allegiance to the government, fear of retaliation or concern that the country could devolve into chaos or extremism.

The government has warned that unrest will lead to sectarian violence of the sort that has plagued its neighbors, Iraq and Lebanon.

But activists said they planned to join with protesters from other towns regardless.

“The question is, how effective will they be with the army involved now,” Ziadeh said. “They’ve never been involved at this level before.”

More than 40 people have been detained in the past two days, activists said, including a lawyer in the city of Hasakah who tried to test the new law Thursday by going in person to the governor of the Hasakah region to apply for a permit to demonstrate. He was arrested and has not been heard from since, Ziadeh said.

“The government said that we have to get permission, so he said, ‘OK, I’ll go get permission’ — and this is the answer.”