A crash involving three vehicles forced the closure of the southbound 110 Freeway in Highland Park Sunday morning.

The crash occurred around 7:20 a.m. near Pasadena Avenue. Three people in their 40s and 50s suffered serious injuries, according to the Los Angeles Fire Department. 

Video from the scene showed wreckage of the vehicles scattered across the freeway, along with leaves and debris from a tree that was struck.

As of 8:15 a.m., it was unclear when the freeway would reopen. LAFD urged drivers to seek alternate routes.

The cause of the crash was under investigation.