The big picture: While Cruz has no direct control over the power situation in Texas as a federal lawmaker, outraged critics argued the senator should be stateside trying to find solutions for his constituents.
He further described Cruz as "an enemy to our democracy" for challenging the certification of the Electoral College vote before and after the January 6 attack on the U.S. Capitol and as "an enemy to our state" for "jetting off to Mexico while Texans remain dying in the cold".
More than 2.5 million Texas homes and businesses are still without power as frigid temperatures have devastated the state's power grid.
After the photos went viral, users - including celebrities - took to Twitter to slam Cruz for traveling to the island while leaving his state to fend for its self.
His office did not immediately respond to a request for comment from the BBC.
The news comes after hours of speculation on Wednesday night about the senator's whereabouts after photos of him and his family at the Houston airport appeared on Twitter, met with huge criticism as an estimated half a million Texans were left without electricity amid freezing temperatures.
Photographs of Cruz, R-Texas, at an airport began circulating on social media late Wednesday, with people alleging that the senator had left the state for Cancun amid a major crisis.
Meanwhile, Punchbowl News reported Thursday that a person appearing to be Cruz is ticketed for a flight from Cancun to Houston later Thursday.
The tweet included a photo of Cruz walking down the aisle of a plane he was boarding.
"Unless we hold those responsible accountable for what they did, and yes, that means Donald Trump, but it also means the junior senator from the state of Texas, who I understand is vacationing in Cancún right now when people are literally freezing to death in the state that he was elected to represent and serve", O'Rourke said in an interview with MSNBC. Almost 500,000 customers in Texas remained without power Thursday morning. The Texas Democratic Party has made multiple calls for Cruz to resign. Roughly 485,000 Texans are still without power, according to PowerOutage.US. Drinking water is limited and in many areas, "boil notice" warnings have gone into place, advising that it's not safe to drink water out of the tap without boiling it first.
In Austin, some hospitals faced a loss in water pressure and in some cases, heat.