(CNN) -- Syrian tanks have withdrawn from residential areas in cities, but snipers remain a threat, and killings are still occurring, the head of the Arab League said Monday.
"There is still gunfire, there are still snipers, and we hope that all that will disappear," Nabil el-Araby said in Cairo, adding: "There is gunfire from various directions, which makes it hard to tell who is shooting.
"There is no doubt that killing is ongoing, but I can't pinpoint the numbers," he said.
Syrian government tanks have moved to the outskirts of cities, he said after an advance team of Arab League monitors returned from the violence-wracked country and began preparing an initial report.
That report will be completed "in the coming days" and presented to the Arab League's foreign ministers, who will decide on what action to take, el-Araby added. "We will not wait for the mission to end" before taking action, he said.
Arab League observers entered Syria last week after the United Nations estimated that 5,000 people had been killed since March in an uprising against the government.
President Bashar al-Assad's government says it is cracking down on armed terrorists.
The Arab League aims "to provide protection to Syrian civilians," el-Araby said Monday, adding that it was asking for a cease-fire and for the names of detainees in Syrian prisons.
Nearly 3,500 prisoners have been freed, he said.
The Arab League has placed more than 70 monitors in six cities, and the number of observers will soon exceed 100, el-Araby said.
The increase comes despite a call by an Arab League adviser to pull the observers out.
The head of an advisory board to the Arab League called Sunday for the withdrawal of observers from Syria, saying the mission has allowed Syrian officials to continue a brutal crackdown on protesters.
"What is happening allows the Syrian regime a cover for the exercise of its inhumane practices under the Arab League's watch," Ali Salem al-Deqbasi said in a statement, according to Egypt's state-run MENA news agency.
Al-Deqbasi heads the Arab Parliament, an advisory board to the Cairo-based Arab League.
As the fact-finding mission continued Monday, at least 26 people, one of them a girl, were killed in Syria, according to a network of opposition activists.
Eleven people were killed in Homs, six in Idlib, five in the Damascus suburbs, three in Hama and one in Aleppo, the Local Coordination Committees of Syria said. The organization said a child was among the "martyrs."
Between Tuesday, when Arab League monitors entered Syria, and Sunday, 315 people -- 24 of them children -- were killed, the activist network said Sunday.
Meanwhile, the state-run Syrian Arab News Agency said Monday that the bodies of 11 "army and police martyrs killed in the line of duty by armed terrorist groups" were buried.
CNN cannot independently verify accounts of violence or reports of casualties in Syria because al-Assad's government has restricted international journalists from working freely in the country.
Al-Assad's crackdown on anti-government protesters calling for his ouster began in mid-March. The Syrian government has repeatedly blamed "armed terrorist groups" for violence during the uprising.
The Local Coordination Committees of Syria, which has a network of contacts across Syria and organizes and documents anti-government protests, said that more than 5,800 people were killed in 2011 during the crackdown on opposition protests.
Amateur videos posted online purport to show Arab League observers.
One video posted Friday purported to show residents of the southwestern city of Daraa telling a monitor about a man who they said had been a victim of torture.
Another video purported to show that same monitor saying he had witnessed snipers firing in the city, which has been a flashpoint for clashes between anti-government protesters and security forces.
On Sunday, the head of the Arab League monitors' mission said observers had not seen sniper attacks.
"We are monitoring the alleged presence of snipers on buildings, but (there is) no evidence of that yet," said Lt. Gen. Mohamed Ahmed Mustafa al-Dabi.
But el-Araby offered a different view Monday. "There is constant gunfire from building rooftops," he said. "We can't identify its exact origin, but we know there are snipers on rooftops."
The Arab League, the United States, the European Union and Turkey have condemned the government crackdown and initiated sanctions. But Russia and China have stood in the way of a strong U.N. Security Council resolution toward the Syrian government.
Last month, al-Assad agreed to a peace initiative with the Arab League that calls for security forces to withdraw from cities, release detainees and end violence. Part of the agreement calls for Arab League observers to monitor whether the government abides by the initiative.
CNN's Roba Alhenawi, Amir Ahmed and Mohammed Jamjoom contributed to this report.