DENVER — A sport-utility vehicle plunged more than 300 feet off a snowpacked mountain highway on Tuesday, killing a pregnant woman and her fetus, the Colorado State Patrol said.

The patrol said the driver lost control on Interstate 70 about 50 miles west of Denver, near the Eisenhower Tunnel, during a spring storm that dumped a foot of snow in mountains.

The storm also drenched Denver-area highways with rain during the morning rush hour.

The patrol said Analisette Sapien of Frisco, who was seven months pregnant, was a passenger in the SUV and was not wearing a seat belt. Her age wasn't available.

Another passenger, Zulma Fuller, 33, suffered serious injuries and the driver, Jose Bucio, 28, suffered moderate injuries. Both were wearing seat belts and both are from Frisco, the patrol said.

The patrol said neither alcohol nor drugs were believed to be a factor.

A tractor-trailer rig crashed and spilled 12-packs of beer onto a highway in the west Denver suburb of Wheat Ridge, and police said slick roads may have been a factor.

The truck overturned while entering Interstate 70, police spokeswoman Lisa Stigall said. Cans of Keystone Light spilled onto the highway and down an embankment.

The driver was taken to a hospital but was not seriously injured, she said.

Stigall said the truck's speed and a sharp curve on the on-ramp may also have contributed to the crash.

The National Weather Service said a foot of snow fell in Evergreen about 15 miles west of Denver. Tabernash, about 50 miles northwest of Denver, reported 10 inches.

Arapahoe Basin, the only major ski resort still open in Colorado, reported 5 inches of new snow.

On May 2, a spring snowstorm brought high winds and blizzard-like conditions to northeast Colorado.