Hurricane Marie was pounding heavy waves into Mexico's Pacific coast Monday, where three fishermen went missing after their boat capsized.

The eighth hurricane of the eastern Pacific season, Marie briefly hit category five, the most powerful storm rating on the Saffir-Simpson scale, before calming slightly.

"Unfortunately, we have three missing fishermen," said Wenceslao Petit, director of civil protection in the tourist hub of Los Cabos on Sunday.

The navy went to the rescue of the Tio Chori, which went out to sea with seven fisherman aboard. The boat overturned after being rammed by heavy waves caused by the storm, but four of the fishermen were able to swim to shore.

A ground and air search was underway for the three still missing.

The civil protection agency declared a state of emergency in the Los Cabos region.

Marie was packing maximum sustained winds of 145 miles (230 kilometers) per hour, according to the latest bulletin from US forecasters.

But the Miami-based National Hurricane Center (NHC) suggested the worst may soon be over, forecasting "some fluctuations in intensity" Monday morning, and "a general weakening trend" starting at night.

Marie was far from land -- some 465 miles (750 kilometers) southwest of Mexico's Baja California peninsula -- moving west-northwest at 12 miles per hour.

No coastal storm watches or warnings were in effect, but the NHC warned powerful waves were slamming southwestern Mexico and Baja California Sur.

"These swells are likely to cause extremely dangerous life-threatening surf and rip current conditions," the forecasters warned.

In Mexico, the national weather service said Sunday the storm was bringing heavy rains, hail, and thunderstorms, to the states of Baja California Sur, Nayarit, Jalisco, Clima, Michoacan and Guerrero, on the Pacific Coast.

It urged caution in the heavy winds and churning waters, and to remain alert for landslides, mudslides and overflowing rivers.