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The New York Stock Exchange resolved a "critical" technical issue Wednesday that led to 199 ticker symbols being suspended for trading.
"NYSE experienced a technical issue in one trading unit, which affected a subset of symbols listed on our Market Status website here. All open orders, including MOC and LOC orders, were cancelled. Trading has resumed in those symbols at 1:17 pm ET and all systems are now operating normally," the NYSE said in its systems status page.
The issues affected one trading unit with the same symbols. Trades in those symbols continued to come through other market centers.
Both the Nasdaq and BATS stock exchanges had declared self-help against the NYSE amid the technical problems. A self-help exception allows trading centers to bypass an automated trading center that is experiencing system problems, according to the SEC.
NYSE believes the stocks affected were traded by Citadel KCG at Post 5, said NYSE spokesperson Kristen Cause. The area of the trading floor was roped off as the issue was addressed.
Cause told CNBC that she believes the issue is linked to the NYSE's own system but it will continue to look for the root cause.
— Reuters contributed to this report. This story has been updated to reflect a more precise definition of self-help.
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