A large pothole on an Arcadia freeway onramp damaged several vehicles and prompted a traffic alert, according to the California Highway Patrol.

CHP said multiple vehicles sustained flat tires after hitting a pothole on the onramp from Foothill Boulevard and Baldwin Avenue to the westbound Interstate 210. 

Several vehicles required tow trucks to assist stranded motorists, according to CHP. A SIG Alert was also issued for at least 30 minutes.  

Caltrans was responding to the scene to repair and fill the pothole.