MANILA, Philippines ? Robbers broke into a pawnshop in Taguig City over the weekend and made off with P5 million worth of cash and jewelry.

Police found two empty tanks of acetylene, a corrosive gas used in welding and cutting metal, inside the PMC Pawnshop at 2 Mayor Tanyag St., Zone 6, Barangay Signal Village Monday morning.

The robbers are believed to be members of the Acetylene Gang, a group which uses acetylene to bore holes in the vaults of establishments they rob.

Purificacion Concepcion, the pawnshop owner, told the police that the thieves took P5 million worth of cash and jewelry stored in the vault.

Concepcion discovered the theft when she opened the pawnshop at 7:30 a.m. Monday.

According to case investigator PO2 Melvin Garcia, the robbers rented a vacant apartment beside the pawnshop and then dug a hole in the wall next to the establishment.

A man who identified himself as Oliver Eskag gave a downpayment of P60,000 for the rent of the apartment a week before the robbery occurred.

Eskag reportedly told the owner of the apartment that he planned to convert it into an Internet shop.

?It seems the suspects conducted a week-long surveillance before striking during the weekend,? Garcia said.

The incident was the second pawnshop robbery in Taguig City this month; on May 18, unidentified men also broke into the Carmen Pawnshop at 10 Liwayway St. in Barangay Sta. Ana.

Garcia said they were looking into the possibility that the same group was behind the two incidents because both used acetylene to force their way into the establishments? vaults.

?It?s probably the same group because the modus operandi is the same. Someone rented a vacant space near the pawnshop and then struck during the weekend,? he added.