ANKARA, Turkey — Officials at Turkey's Foreign Ministry say two Syrian air force generals have defected and crossed the border.

The defection comes as rebels besiege the military air base of Mannagh near the Turkish border.

The officials said Friday the two generals were "regional Syrian Air Force commanders" and are now in a camp where army defectors stay in Turkey.

They refused to give the generals' identities or say how they escaped from Syria. They spoke anonymously as they were not authorized to talk to the press.

The defection comes days after the commander of Syria's military police Maj. Gen. Abdul-Aziz Jassem al-Shallal defected to Turkey.

Al-Shallal is among the most senior members of Assad's military to defect.

Dozens of Syrian generals have defected since the country's crisis began in March 2011.