Syrian government forces on Thursday tightened their siege of the dissident central province of Homs, a day after killing more than 100 people in heavy shelling, opposition activists said.
"More than 1,000 troopers backed by dozens of tanks are now positioned on the outskirts of Homs," Omar Homsi, an activist based in the area, said by satellite phone, DPA reported.
He said the shelling continued Thursday on the districts of Baba Amr, al-Bayyada and al-Khalidiyeh in Homs, killing at least five people.
"This signals preparations for a major onslaught on the areas where activists and defectors are based," Homsi said.
The Syrian opposition has called for Arab and Western countries to intervene to immediately stop attacks on residential areas.
On Wednesday, UN Secretary General Ban Ki-moon said Arab League head Nabil al-Arabi had informed him that the pan-Arab organization planned to send a monitoring mission back to Syria and asked for UN help.
The Arab League suspended its monitoring mission to Syria on January 28 because of rising violence.