The United Nations' top human rights official has called for a thorough investigation into allegations of widespread abuses in Syria during the government's crackdown on dissent.
High Commissioner for Human Rights Navi Pillay also renewed her call on Wednesday for Syria to grant access for a U.N. fact-finding mission. Her office has released a report citing allegations against Syrian forces that include an excessive use of force against civilians, arbitrary detentions and torture.
It says the most "egregious" allegations concern the use of live ammunition against civilians.
The U.N.'s report comes at a time when Syria's military has been widening its crackdown on opposition in an northern region near Turkey's border - a move that has prompted thousands of Syrians to flee to Turkey.
On Wednesday, military forces were poised to enter Maarat al-Numan. Witnesses and activists said tanks have surrounded the northern town.
Syrian forces remain in control of the nearby flashpoint town of Jisr al-Shughour after pushing into it on Sunday.
Meanwhile, Turkish officials say the number of Syrians who have crossed the border has swelled to 8,500. Turkish Prime Minister Recep Tayyip Erdogan is to meet with a Syrian envoy on Wednesday to discuss ways to end the turmoil and the tide of refugees into Turkey.
Syria is urging people who fled to Turkey to escape the crackdown in Jisr al-Shughour to return home. The official news agency SANA said that "calm and security" had been restored in the town and surrounding area.
Also Wednesday, thousands of loyalists to Syrian President Bashar al-Assad staged a rally on the outskirts of Damascus, where they unfurled a huge Syrian flag measuring 2.3 kilometers.
In Washington, U.S. State Department spokesman Mark Toner said the option of imposing additional sanctions on Syria remains a possibility.
Rights activists say about 1,300 civilians and 340 security force members have been killed since the protests against Assad's government began in mid-March. Syria has banned most foreign journalists, making it difficult to verify accounts of events.
Some information for this report was provided by AP, AFP and Reuters.
