The Arab League chief says snipers and gunfire remain a threat in Syrian cities despite the presence of League monitors.

Speaking in Cairo Monday, Nabil El Araby called for an immediate cease-fire in Syria. He said Syria's military has withdrawn from inside cities, but snipers are still killing people and making it difficult to distinguish who is shooting whom.

The Arab League has sent monitors to Syria to check on its compliance with a League plan for peace after a nine-month crackdown on anti-government protests. The plan requires the Syrian government to remove security forces and heavy weapons from the streets, start talks with the opposition, free political prisoners and allow monitors into the country.

The Arab League chief said 70 monitors are in six Syrian cities, with 30 more monitors joining them soon. He said the monitors have secured the release of about 3,500 prisoners in Syria so far.

Activists say more than 150 people have been killed across Syria since the observers began their mission last week.

On Sunday, the Arab Parliament, an advisory body of the Arab League, said the observers are failing to prevent government troops from killing civilians, including children.

The group's speaker, Ali al-Salem al-Dekbasi, said the monitors should pull out immediately, given the ongoing violence. The 88-member parliament operates separately from the Arab League, and its recommendations are nonbinding.

The United Nations estimates that more than 5,000 people have died in Syria's violence since March during a crackdown on protests inspired by the Arab Spring democracy movement. The government of President Bashar al-Assad claims armed terrorists are driving the revolt.

Syrian authorities, under increasing international pressure, agreed last month to allow the Arab League monitoring mission. The deal required the government to give monitors freedom of movement through most of the country except for sensitive military sites.