Police in California are still looking for a motive after a gunman shot and killed nine people. The victims included some of his co-workers.
The gunman worked at a rail yard in the city of San Jose.
Early Wednesday, he started shooting his coworkers with two semiautomatic handguns. Police believe that he then shot himself.
At the same time, firefighters responded to a call that a house was on fire. The home turned out to be the gunman's. Police believe he may have ignited the fire with an explosive device.
Police found explosive materials in the man's locker. Members of a bomb squad searched the rail yard for hours but didn't find anything else.
US President Joe Biden urged Congress to end what he called an epidemic of gun violence. He said Americans can, and must, do more.
The Gun Violence Archive reports that this was the 232nd mass shooting in the US this year.