Officers were investigating reports of shots fired on the northbound 2 Freeway in Glendale late Tuesday after a stolen vehicle crashed and snarled traffic, the California Highway Patrol said.
The vehicle crashed near Foothill Boulevard, where one person was detained, Officer Alex Rubio said. Another suspect was being sought.
Rubio said the vehicle was stolen in a possible carjacking. He said it was not immediately clear whether shots were actually fired.
No other details were immediately available.