Officers received a call for help at 11:44 p.m. Thursday from a home in the 500 block of east Norman Avenue.
Police say two people were tied up and blindfolded as the suspects ransacked the home. When three more people arrived at the home, they too were tied up.
"I walked into the house and somebody had just robbed me. They ran to me and put my face down to the ground," said one of the victims, only identified as "Cindy."
There were five suspects, and at least one of them was armed with a handgun, police say.
"They used the gun to scare me," said Cindy. "They said, 'Move, you have to cooperate, otherwise I will hurt you.'"
Cindy says she was tied up with zip ties and her eyes were taped shut.
Two male victims were struck by the suspects and sustained minor injuries. They were treated at the scene by Arcadia Fire Department paramedics. Three female victims were not harmed. All of the victims are adults, police said.
The suspects took off with the victims' passports, electronic devices, jewelry and cash. Car keys were also taken, but no vehicles were stolen.
The investigation is ongoing. Anyone with information is asked to call Arcadia police at (626) 574-5150.