The city has asked for assistance from the Federal Communications Commission in determining who was behind the hack.
The FCC was notified to assist in identifying the source of hack, according to city officials.
Dallas' 156 sirens, normally used to warn of tornadoes and other risky weather, were triggered at 11:42 p.m. CDT on Friday.
The incident, initially labeled a "system malfunction", sparked an avalanche of anxious posts on social media and calls to the emergency 911 system.
Vaz said he expects the emergency siren system to be back in operation by Monday afternoon.
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Walker said there was "great consensus" on high-risk pools for people with pre-existing conditions, but he didn't go into detail. Lower insurance premiums, Meadows said, "has been, will be, always will be" the primary objective.
Many people, naturally, found the sirens unsettling and some took to Twitter to post video of the incident while the city collectively wondered what impending doom the sirens might be warning of.
WFAA viewers reported sirens sounding in other communities besides Dallas. Later Saturday morning, Garland Police sent out a tweet to clarify the situation. "We had no malfunction". "Right now, our priority is to work on reactivating our system".
"At this point, we can tell you with a good deal of confidence that this was somebody outside of our system that got in there and activated our sirens", he told reporters.
Dallas Mayor Mike Rawlings promised the perpetrator would be found and prosecuted.
A city spokesperson says the sirens are going off due to a system malfunction and emergency crews are working to fix the problem.