The main gauge of Tehran Stock Exchange dropped more than 7,000 points for day to 320,211, sending TEDIX 2.1% lower.
Selloff pressure for stocks of Bank Mellat in the early hours of trading bode ill for investors long waiting for a market correction.
The lender has led top-performing companies in the stock market since its symbol ticker reopened on Wednesday, Financial Tribune reported.
There was a massive sell-off in 72 symbol tickers a quarter to closing trading session at 12:30 p.m. local time, according to Donyaye Bourse website.
The market featured noticeable investor unwillingness to participate in the trades amid expectations of further bearish trends.
Market Performance
The TSE's main index TEDPIX lost 7,094.06 points or 2.17% on Sunday to end trading at 320,211.7.
About 5.35 billion shares valued at 24.41 trillion rials ($214.15 million) changed hands at TSE for the day.
Trading at TSE and over-the-counter Iran Fara Bourse starts on Saturday and ends Wednesday.
Ardakan Industrial Ceramics Company was the biggest winner as its shares went up 5% to 19,951 rials per share.
Iran Casting Industries incurred the biggest loss among all TSE-listed companies and went down 9.53% to 2,060 rials per share.
National Iranian Copper Industries Company contributed the most to the benchmark's fall, followed by Mobarakeh Steel Company, Telecommunication Company of Iran, and MAPNA Group.
Barakat Pharmaceutical Group gave the biggest boost to the benchmark index, followed by Sepahan Oil Company, and Behran Oil Company.
The Price Index lost 1,906.64 points, or 2.17% to close at 86,063.9.
The First Market Index was down 5,936.05 points, or 2.50% to post 231,802.0. Second Market Index was down 10,922.69 points, or 1.64% to reach 655,297.3.
The Industry Index went down 6,042.24 points or 2.09% to register 282,966.8.
IFX Down 1.58%
Iran Fara Bourse main index IFX lost 67.13 points or 1.58% to close Sunday trade at 4,187.95.
About 1.68 billion securities valued at 10.46 trillion rials ($91.80 million) were traded at the over-the-counter exchange for the day.
Middle East Mines & Mineral Industries Development Holding Company had the highest number of traded shares and trade value as 370.88 million of its shares worth 1.96 trillion rials ($17.26 million) were traded.
Marun Petrochemical Complex, Goharzamin Iron Ore Company and Esfahan Steel Company had the most negative impact on IFX.
Jahrom Power Plant Development Company gave the biggest boost to IFX, followed by Damavand Power Generation Company, and Iranol Oil Company.