Westbound Interstate 80 near Hercules closed due to police activity

All westbound lanes of Interstate 80 in Contra Costa County remain closed Thursday afternoon due to police activity that began hours earlier, authorities said.

Caltrans said around 9:10 a.m. that westbound I-80 is closed at the Hercules offramp, leading to a backup that is stretching several miles to the Carquinez Bridge. Meanwhile, the left lane of eastbound 80 is closed at Pinole Valley Road.

According to the California Highway Patrol, the alert stems from an earlier traffic collision. 

The Hercules Police Department said in a statement that their officers were not involved with an incident, but they are assisting with managing traffic. Police added that there was no threat to the community.

Additional details about the incident were not immediately available.

As of noon, the westbound lanes of the freeway remained closed. Westbound traffic is being diverted at Willow Avenue, officials said. 

There is no estimated time to reopen the lanes and drivers are being urged to find alternate routes.