An Arab League observer mission is due to arrive in Syria today, as activists report new deaths in the government's crackdown on a nine-month uprising.
Opposition activists said at least six people were killed by heavy machine gun fire and mortar shells fired by government troops besieging the restive Baba Amr district of Homs, a city in the centre of the country.
The Arab observers are tasked with monitoring Syria's compliance with an Arab plan to end the crackdown on dissent. The UN says more than 5,000 people have been killed since March.
The opposition urged the observers to head immediately to Homs to witness the crackdown there.
The Baba Amr district has been a centre for anti-government protests and army defections and has been under attack for days.