The central bank has detected 57,380 counterfeit bank notes in circulation during the first half of the year, but police warned on Tuesday that money counterfeiting usually peaks in the days before, during and after Ramadan.

The Muslim fasting month is often seized upon as an ideal moment to use counterfeit money because of the increase in transactions as people buy more food, jewelry, clothes and gifts.

According to Bank Indonesia, the number of fake bank notes detected declined from 70,104 in the first half of last year.

The 57,380 counterfeit notes included 33,272 counterfeit Rp 100,000 notes and 20,217 counterfeit Rp 50,000 notes. Their total face value was at least Rp 4.34 billion ($512,000).

Most of the fake notes, a total of 48,844, were in circulation in Jakarta.

Wijayanti Yuwono, head of Bank Indonesia’s money distribution bureau, told the Jakarta Globe that although counterfeit money distribution apparently declined this year, people needed to remain vigilant.

Jakarta Police spokesman Sr. Comr. Baharudin Djafar said the counterfeit money was usually brought into circulation in crowded places.

“The distribution is usually done during transactions that take place in a crowded place and when a quick transaction is required, like at a toll road entrance or in mall or a market, where the victims do not have time to check the money they received,” he said.

“A quiet place can also become a target for distribution, though, such as food or beverage stalls in small towns where the victims do not have the necessary equipment to detect counterfeit money,” he added.

Baharudin said Ramadan and other major religious events offered an ideal opportunity for money counterfeiters because people spend more than they normally do during those times.

Wijayanti said that before any transaction involving a large sum, the receiving party should first have the money checked at the nearest bank.

If anyone is not sure whether the money in question is genuine, she said, it would be better to bring it to a bank because fake bills can be detected there.

However, she said there were easy ways to detect if bank notes were genuine or not, and any citizen could learn them.

“First of all, we can feel the texture of the bill. Counterfeit bank notes [usually] are printed on glossy paper and they don’t have a code for blind people,” she continued. “Secondly, counterfeit bank notes often have brighter or darker colors than genuine money.”

She added that genuine notes had a security thread, miniature text and a watermark image usually looking to the right, while the watermark image on counterfeit ones look to the left.

“The last and easiest way to identify real notes is by looking at the optically variable ink on the Bank of Indonesia symbol. When the money is moved, the color changes, like from yellow to green,” she said.

Wijayanti said the central bank was cooperating with the National Police to eradicate counterfeit money distribution.

“We do not know exactly how many counterfeit bank notes are in circulation because we only record it based on reports to banks or the police,” she said.

It is common during Ramadan for people to sell small-denomination bank notes — such as Rp 2,000, Rp 5,000 and Rp 10,000 — as give those to children during festivities after the end of the fasting month.

“There are many people who need smaller bank notes. I earn an extra Rp 10,000 for every Rp 100,000 in smaller notes that I sell,” Murniani, 33, who runs such a business in Jakarta’s Kota Tua, told the Globe.