(CNN) -- Arab League officials decided Sunday to bolster the alliance's fact-finding mission to Syria, where thousands have been reported killed by security forces despite ongoing international pressure to halt the violent suppression of popular unrest.
In a statement, released after a meeting of officials in Cairo, the alliance once again "strongly condemned ... acts of violence against civilians."
It reiterated the league's call for Damascus to completely stop acts of violence in order to protect civilians, free political detainees, remove tanks and weapons from cities, and allow outsiders, including the media, to freely travel around Syria and document what's happening.
That includes the 165 observers from the Arab League who are now in the Middle Eastern country. That number will now increase, after the Arab League on Sunday called for more observers and more equipment for this mission.
While this effort does not have a mandate for peacekeeping or to stop the conflict, it is tasked with verifying that Syria complies with the Arab League's action plan.
The league stated that the success of the mission -- in terms of finding out the real facts within Syria -- depends on getting openness and full cooperation from the Damascus-based government.
A spokesman for Syria's foreign ministry said Sunday that his nation's government hasn't hidden anything from the Arab League's monitors.
"We let them move freely anywhere. We have provided all the things they need," spokesman Jihad Makdissi said.
Arab League officials urged opposition parties Sunday to increase their efforts to seek a political solution to the impasse by uniting under one government. The regional alliance also acknowledged "partial" steps taken by Syria's government to address the situation, as recommended by the league.
Human Rights Watch noted that League Secretary General Nabil el-Araby has said that "Syria has already taken some steps under the terms of the agreement, withdrawing heavy weapons from Syrian cities, and releasing about 3,500 prisoners."
The advocacy group also highlighted what is says are examples of Syria not abiding by the league initiative, including continued attacks by security forces on peaceful demonstrators.
Early morning clashes between government security forces and army defectors killed at least 11 people Sunday in the village of Basr al-Harir in Daraa, according to the Syrian Observatory for Human Rights, a London-based opposition human rights group with contacts throughout the country.
Later Sunday, opposition activists from the Local Coordination Committees of Syria said that at least 21 people were killed in attacks throughout the country. The LCC's tally listed 14 deaths in Homs, five in the Damascus suburbs, one death in Deir Ezzor and one death in Daraa.
CNN cannot independently confirm events inside Syria because the government has restricted activities by international journalists.
The Syrian government crackdown began in mid-March in Daraa. Last week, human rights groups asked the Arab League to initiate action against President Bashar al-Assad's government. They accused Syria of failing to comply with efforts to end the 10-month-long crackdown.
The Arab League fact-finding mission under way in the nation is part of a larger initiative to end security forces' attacks on peaceful protesters. Death estimates range between 5,000 to 6,000.
Residents say attacks have continued during visits by Arab League officials, but at later times.
Most shelling occurs after officials have gone back to their hotels, a resident in the besieged city of Homs said.
"They take the leaguers where they want," he said Saturday. "These are massacres. We have tens dying daily. Stores are closed ... civilian life is at a halt."
Syria's interior ministry has vowed to "strike with an iron fist" anyone who threatens the nation's security after two car bombings in the capital in as many weeks.
The government has blamed the attacks on terrorists while the opposition points fingers at al-Assad's government.
CNN's Nic Robertson, Ben Wedeman and Joe Sterling contributed to this report.