Mexican authorities went on high alert Wednesday as Hurricane Dora upgraded into a Category 4 storm off the country's Pacific coast.

The Mexican National Meteorological Center, citing initial reports, said the hurricane had caused flooding in the southern states of Guerrero, Oaxaca and Chiapas, resulting in some damage.

There were no immediate reports of casualties, but local residents were urged to be cautious, and Mexican emergency personnel had been put on full alert.

The Miami-based U.S. National Hurricane Center (NHC) reported that at 5 p.m. local time (2200 GMT), Dora was located about 300 km southwest of Guerrero's Ixtapa-Zihuatanejo beach resort, and packed winds of over 215 km per hour.

"Some additional strengthening is forecast during the next day or so," the NHC said, adding the extremely dangerous major hurricane is "likely to cause life-threatening" conditions along the coast.

The current forecast did not see a landfall as Dora raged northwest, but the storm was already whipping up waves as high as 3.96 meters off Mexico's southwestern shores.