Five houses were ransacked in Batam while police were busy working to safeguard Christmas Eve celebrations on Saturday.
Three of the houses were in the Kurnia Djaja Alam housing complex, and the other two were in the Plamo Garden complex.
Among the items stolen were LCD televisions, laptops, jewelry and money.
Besides stealing property, the thieves also left the houses in a mess.
Plamo Garden housing security officer Udin said he had first noticed something was wrong when he saw that the front door of the house owned by Surendro was open on Saturday evening at around 11.30 p.m. Udin immediately reported this to Surendro's neighbours.
The security grill and front door had been forced open with a crowbar, and possessions were strewn about the house, he said.
Batam Kota Police chief Adj. Comr. Heryana, who inspected the location immediately, said the two thefts at Plamo Garden had been inside jobs because the thieves had known the whereabouts of the valuables.
"The thieves seemed to know where to look, because they left the rooms untouched," Heryana said, as quoted by tribunnews.com.