Jakarta  - A group of eight robbers wearing nothing but their underwear robbed an Indonesian businessman's house in West Java's Banten province and stole cash and valuables worth more than 54,000 dollars, a local media report said Tuesday.

The incident took place early on Monday when the robbers entered a house in Banten's Tanggerang district, just west of Jakarta, The Jakarta Post reported.

Three of the robbers broke into the bedroom where two house maids were asleep. While the three robbers tied the two maids with the bed-sheets, five others went to the second floor of the house.

The house's owner, Sudojo, 60, was not at home while his wife, Catrin, 55, was sleeping when the incident took place.

"One of the robbers held a machete to my neck," Cicih, one of the maids, was quoted as saying.

The robbers took a set of diamonds, a Rolex wristwatch, a bank account book and 2 million rupiah (217 dollars) in cash from the couple's safe, bringing a total of 500 million rupiah (54,345 dollars) in losses.

The case is being investigated by Tanggerang district police, who gave no explanation why the robbers wore only underwear. (dpa)