Turkish police have unearthed a large cache of weapons buried underground by the pro-coup soldiers in a security operation on Sunday in Istanbul's Riva district.

During the operation, a pro-coup major and a sergeant were detained. Seven M16 and four MP5 rifles and ammunition were also seized.

Istanbul's office of the public prosecutor and its bureau of terror opened an investigation over a possible "coup and civil war attempt."

Security sources stated that weaponry captured by pro-coup soldiers were buried underground in order to be used against Turkish people in a new coup attempt.

Military troops loyal to the government, along with police units and millions of Turkish citizens, have succeeded as of Saturday morning in quelling a coup attempt, launched by a small military junta-linked to the Gülenist Terror Organization (FETÖ), starting from mid-afternoon on Friday.

At least 2,839 pro-coup members of the military, including 29 colonels and over 40 generals, have been detained across Turkey, the Ministry of Interior said Saturday.

Turkey's top judicial body HSYK also ordered the detention of 2,745 Gülen-linked judges and prosecutors on Saturday while two members of the Constitutional Court were detained for involvement in the coup attempt.As a result of the attempted coup, 161 people were killed, including 41 police officers and 47 civilians, while 1.440 others were injured. Some 104 pro-coup figures were also killed.