One such hard-hit area was in Matamoros, across the Rio Grande from Brownsville, Texas, where Dolly unleashed strong winds, heavy rains and rampaging floodwaters and many had to make the hard choice to whether to flee their battered homes or try to ride it out, the San Antonio Express-News reported.

One was Bertha Casares, whose evacuation decision was a tough choice.

"We didn't think it was going to be a big deal," she said after wading out of her house in water up to her hips, her children and elderly mother in tow. "Life is worth more than possessions."

Arcadio Escobar, one of the police officers on hand to help evacuation, plucked 120 people from the water before the flood got too high and he ran out of gas.

"There are still a lot of people in their houses and they are asking help," said Escobar, taking notes from evacuees on the locations of others in distress.

The government deployed 1,800 soldiers and state police to Matamoros to prevent looting.

Mexico's state-owned oil company, Petroleos Mexicanos, evacuated 66 workers from an offshore rig near the Tamaulipas coast, the company said.