The California Highway Patrol is investigating three fatal crashes that occurred during the last week in the unincorporated area near Livermore.

One crash involved a wrong-way freeway driver. Another involved a motorcyclist. The third, on Tuesday, involved a solo vehicle that may have been speeding before it hit the center divider.

In the first crash Sunday, Gabriella Perez-Ramirez, 24, of Manteca died when her white Buick LeSabre crashed into an oncoming vehicle while driving the wrong direction on I-580 near North Livermore Avenue.

The CHP said alcohol appeared to play a role in the crash, which occurred about 6:20 a.m. as Perez-Ramirez drove west in the eastbound lanes until she crashed into a black Nissan Altima. Several other crashes occurred as a result.

According to the CHP, Perez-Ramirez did not appear to be wearing a seat belt at the time of the crash. The female driver in the Nissan was taken to Eden Medical Center in Castro Valley. She suffered major injuries but was expected to recover, the CHP said.

In the second crash, motorcyclist Gilbert Chang, 48, of Brentwood was killed about 9 p.m. Sunday when he crossed into oncoming lanes on Vasco Road, south of the Vasco Landfill, and crashed into a Chevrolet Blazer.

According to the CHP, Chang was riding north at an unknown speed when he crossed over the double-yellow lines and collided with the Blazer, which was coming the other direction. Livermore-Pleasanton firefighters pronounced him dead at the scene.

The Blazer’s driver, who was not identified, suffered major injuries and was taken to Eden Memorial Medical Center for care. He was expected to recover.

Although Chang was believed to be at fault for causing the crash by crossing into oncoming traffic, the Blazer’s driver was arrested. By chance, he was suspected of drunken driving.

On Tuesday morning, a motorist initially thought to be speeding while driving on the eastbound lanes of I-580 at Santa Rita Road, crashed into the center divider and was killed. No other information was available from the CHP by deadline.