LOS MOCHIS, Mexico (AP) _ Hurricane Isis slammed into the Mexican mainland early today with 75 mph winds and heavy rain, drenching Sinaloa state. Isis weakened to a tropical storm as it headed north along the Gulf of California toward Arizona.

Winds late Wednesday and early today broke windows, knocked out electricity and littered Los Mochis with downed street posts and tree limbs. The light roof at a local gas station collapsed on a compact car that apparently was unoccupied. Mayor Francis Lopez Brito said one person was seriously injured by a jolt from a downed power cable.

The storm killed one person Wednesday in Baja California Sur state and two people were missing.

Rain poured down today, but with wind speeds dropping to 50 mph, Isis was downgraded to a tropical storm, the U.S. National Hurricane Center in Miami reported.

At 11 a.m. EDT, the center of Isis was about 100 miles north of Los Mochis and 270 miles south of the border city of Douglas, Ariz. The hurricane center said it was moving north about 9 mph.

A few cars sent up a muddy spray as they pressed through water above bumper level in the streets of Los Mochis, a city of 300,000.

Maria Florencia Pedroza, one of about 500 people who fled low-lying neighborhoods, said she went to a Red Cross shelter at a school when water started coming into her house.

Carlos Alberto Villegas used a bucket inside his concrete-block house in a seemingly vain attempt to bail out the lake of water that stood just below the seat of his new sofa. ``It came in so very strong that the house just began to flood,'' he said.

In the port city of Mazatlan, flooding was reported in 15 neighborhoods and the army was helping residents evacuate. Forty-nine shelters have been set up to provide evacuees with food, clothing and medical attention, the government news agency Notimex reported.

Hurricane warnings that had been in effect for parts of the Baja California peninsula were dropped as Isis weakened. But a tropical storm warning was issued for 200 miles of coast from Los Mochis to Guaymas.

With Isis toward the west and Hurricane Earl in the east near the Florida coast, heavy rain fell in much of Mexico.

On Wednesday, Isis cut power and electricity on the Baja California peninsula and forced thousands of residents from their homes.

One woman was killed and her husband was missing after they tried to cross a stream in Los Cabos on the southern tip of the peninsula, said Emigdio Suarez Aguilar, a civil protection official. The body of Josefina Espinosa Agundez, 48, has been recovered. Her husband was presumed dead.

Notimex also reported one man was missing after being swept away by floodwaters Wednesday in Jalisco state.

The hurricane center said 5 to 10 inches of rain was possible in the storm warning area, as well as on the mainland, and residents were warned to watch out for flash floods and mudslides.