Here is a look at Syria's main opposition groups.

Free Syrian Army: The group is comprised of military defectors. It was initially formed to protect civilians but has increasingly gone on the offensive against pro-government forces. Activists say the group launched a high-profile attack Wednesday against a military intelligence complex near Damascus. It used rockets and other weapons to damage the building. Also, the group says it has created a temporary military council that intends to unseat President Bashar al-Assad's government. The group claims to have at least 15,000 members but those claims have not been independently verified. Colonel Riad al-Asaad formed the group shortly after he defected in July.

Syrian National Council: Turkey-based coalition of varying ideologies is Syria's largest opposition grouping. Secular dissident Bourhan Ghalioun announced the council's formation in October and said it rejects foreign intervention. Rejects dialogue with President Assad's government and has been urging him to resign. Has created a general assembly, a general secretariat and an executive committee whose members will chair the council on a rotating basis.

National Coordination Committee: Primarily based in Syria. Wants the government to enact reforms though dialogue and by building new civilian institutions. Headed by Hassan Abdul-Azim, who has been demanding an end to President Assad's crackdown as a condition for any dialogue between the government and the opposition.