They were women like 84-year-old Ernestine Avilar, who was robbed inside her Culver City home in July.
"He said to me, 'If you obey what I want, I won't harm you ... otherwise, I'll kill you,'" said Avilar.
In one of the robber's more recent robberies, along the 1200 block of Ashland Avenue in Santa Monica, he tied up his 90-year-old victim for hours. Like in all other cases, he stole cash and jewelry from her home.
"He was someone who was after very vulnerable people. And whether or not he used a weapon, he could've caused a heart attack, he could've caused horrible things to happen to these old ladies in the middle of the night," said Jack Weiss, Los Angeles City Council.
According to Councilmember Weiss, tips led investigators to the suspect. Authorities say they watched the robber closely until they had enough evidence to make the arrest on Friday.
"This was clearly a bad guy who was patient and who studied his surroundings. So, LAPD got patient, and they studied him and his surroundings," said Weiss.
The suspect is expected to be arraigned on Tuesday.