Syrian rebels have captured parts of a large army base in the north of the country, just west of the city of Aleppo, activists said.
The Britain-based Syrian Observatory for Human Rights said the rebels entered the Sheik Suleiman base on Sunday afternoon after weeks of fighting.
The development indicates the rebels are strengthening their grip on northern areas near the Turkish border. Last month, they captured another large base near Aleppo.
The Observatory said the rebels seized a key sector of the base. Amateur videos released by activists showed gunmen walking inside the base, carrying a jihadist black Islamic flag.
The footage also showed rebels driving around in a captured tank and manning heavy anti-aircraft machine guns. The activist videos appear genuine and correspond to AP's reporting on the events depicted.
The Observatory also reported heavy fighting on the southern edge of the strategic rebel-held town of Maaret al-Numan, captured from government troops in October.
It said rebels ambushed an army unit, killing at least 13 soldiers. The group said Syrian warplanes bombed the town after the death of the solders.
Meanwhile, Germany has expelled four employees of the Syrian embassy in Berlin in a diplomatic move to put pressure on the regime of President Bashar Assad.
Foreign minister Guido Westerwelle said the expulsion of the four, whose identities were not released, sends a "clear sign that we are reducing relations with the Assad government to an absolute minimum".