A building in Hasırlı neighborhood of the Sur district collapsed while 12 soldiers from Special Forces Command were inside. The cause of the collapse is still unknown.
While nine soldiers have been rescued, authorities tried to save three more still trapped under the rubble.
AFAD teams have also conducted search and rescue operations.
Sur is one of the three districts in southeastern Turkey where security forces have been conducting a sweeping operation against Kurdistan Workers' Party (PKK) terrorists to re-establish public order and safety.
Members of the PKK terrorist group, which began its insurgency in 1978 and has killed at least 40,000 civilians in the southeast, resumed its terror activities last summer. They set many government buildings, schools, hospitals, mosques and workshops on fire, set barricades on roads and planted mines on roadsides.
The PKK, considered a terrorist organization by Turkey, the US and the EU, resumed its 30-year armed campaign against the Turkish state in late July 2015.
Since then, more than 270 members of the security forces have been martyred and thousands of PKK terrorists killed in operations across Turkey and northern Iraq.