The truck was carrying migrants who illegally entered Turkey; it toppled near Bayramli village in Van province, according to the official, who asked not to be named due to restrictions on talking to the media.
The exact reason for the accident remains unclear; however, the driver is said to have lost control of the vehicle.
Among the injured were 32 Pakistani, 32 Afghan and six Bangladeshi nationals who were later hospitalized, the source said.
Twelve of them were said to be severly injured.
Security forces are searching for the driver, who escaped from the scene after the accident.
Separately, 43 undocumented migrants were held near the border gate in northwestern Kirklareli province, according to a gendarmerie source.
The migrants, including Pakistani, Iranian, Iraqi, Afghan nationals, were said to be preparing to cross over into Europe using an illegal route when they were apprehended.
Also, in southern Hatay province, 18 Syrian refugees were detained, when they attempted to illegally enter Turkey from Syria, according to a security source.
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