Syrian soldiers have started to plant landmines on the border with Lebanon.
A security source claimed one man has already had part of his leg blown off as he headed over the frontier into Lebanon.
The crossing has been used to smuggle goods and weapons into Syria since the uprising against the regime began in March.
There appears to be no let up in the conflict. Amateur video posted on the internet purported to show fighting on the outskirts of Damascus and in the northern city of Idlib. The images appeared to show soldiers dragging a body along the street.
Activists claim 11 people were killed on Friday across Syria.
The latest violence comes after the government agreed to a peace deal brokered by the Arab League last week.
The 22-nation body is to hold an emergency meeting on Saturday to discuss what to do about what they see as the failure by Damascus to abide by its commitments to withdraw tanks and other heavy weapons from cities across Syria.