-- Authorities in Houston are investigating a couple's mysterious double killing in a secluded section of the city.
The victims' son, who went to check on his parents after not hearing from them since last Thursday, called police from the home Saturday night, the Harris County Sheriff's Office said.
When deputies went inside the home they found Bao Lam and Jenny Lam, both 61, bound and shot to death, the sheriff's office said.
Investigators believe the Lams came home around 8:40 p.m. on Jan. 11 "and were ambushed by suspects as they parked their car in the garage," the sheriff's office said.
"The house appears to be ransacked," Harris County Sheriff Ed Gonzalez told reporters Saturday night.
Firearms and other valuables were missing, the sheriff's office said.
Gonzalez described the Houston home as in a "secluded subdivision" in a gated community, adding that there doesn't appear to be any immediate danger.
Investigators may release a surveillance video clip from the area this week, the sheriff's office said.
"We're asking the public, if you saw anything out of the ordinary, please call the Harris County Sheriff's Office," Gonzalez said.