Syrian activists say a top rebel military leader has been severely wounded by a bomb in the eastern Syrian province of Deir Al-Zoir.
The British-based Syrian Observatory for Human Rights said the commander of the Free Syrian Army, Riad al-Asaad, was targeted in an attack early on March 25.
He has reportedly been transferred to Turkey for treatment.
There were no immediate claims of responsibility for the attack.
Asaad was among the first officers to defect from the Syrian government's forces and join the rebels in 2011.
The news of his injury comes a day after the head of Syria’s National Coalition, Moaz al-Khatib, announced his resignation.
Khatib said in a statement that he had resigned as the head of the opposition coalition in order to work with more freedom outside of official institutions.
The National Coalition said in a statement that it has rejected Khatib’s resignation and asked him to continue in the post.
Qatar, a leading international backer of the opposition, has said it regrets the decision and hopes Khatib will reconsider.
U.S. Secretary of State John Kerry said he also regretted the resignation but said it won’t affect U.S. aid to the opposition.
Khatib's resignation comes two days before an Arab League summit in Qatar.
The meeting is expected to formally decide whether Syria’s seat in the Arab League should be handed over to the opposition.
Syria’s membership in the Arab League has been suspended over the conflict.
Based on reporting by Reuters, AP, and AFP