Two gems traders attending a Bangkok jewellery fair have filed police complaints in two separate jewellery theft cases, one of them involving five Filipino suspects.
In the first case, five Filipinos were arrested after a diamond necklace was reported stolen from the 58th Bangkok Gems and Jewellery Fair in Muang Thong Thani, Nonthaburi, which runs until Sunday.
They were caught by police on Wednesday night shortly before boarding a flight at Don Mueang airport.
The three men and two women are believed to work together as a gang, said Surachet Hakphan, commander of the Tourist Police Division.
Tourist police at the airport found a diamond necklace worth about 300,000 baht in one of the suspect's bags.
Gems trader Paramin Taharian told police that two of the suspects, claiming to be a mother and son, visited his booth at the fair. The son asked to see two pairs of diamond earrings, saying he wanted to buy a pair for his mother.
The woman then distracted him by striking up a conversation, Mr Paramin said.
He believed this was when the man took the opportunity to snatch a diamond necklace from the booth. The two did not buy anything and quickly left.
Mr Paramin said he was unaware the necklace was missing at the time because it was not among the items he showed them. Instead, they took it from a separate display.
He noticed the necklace was missing when checking inventory later, said Pol Maj Gen Surachet.
Officials at Don Mueang spotted the pair around 10pm in the company of three other Filipinos in a departure lounge waiting to catch a flight to Phuket, and eventually to Manila.
They were approached and asked to allow a search.
A search of their luggage revealed a diamond necklace matching the item reported stolen and other jewellery.
All were then detained for further questioning.
The suspects were identified as three men: Ebueza Christian Carpio, 27, Bien Nonoy Mulobuko, 27, Chapoco Florenz Velarde, 65; and two women: Canoy Adoration Carpio, 58, and Mallari Sofia, 56.
Another trader at the jewellery fair, Vanich Wongsuebchart, 27, complained to police Thursday claiming two boxes of gemstones worth about 10 million baht had gone missing while in the care of a courier company.
Mr Vanich said his company had hired a courier firm to transport four boxes of gemstones to the fair on Wednesday. The firm phoned him that morning to say some of the stones had been stolen.
He found two boxes had been forced open and 32 items, including four high-value stones, worth about 10 million baht, had been taken.
According to Mr Vanich, the courier firm told him the theft was likely to have taken place at around 5am. Mr Vanich offered a 500,000-baht reward to anyone who could secure the return of the gems.
Nat Manas, chief inspector of Yannawa police, said the courier firm had also lodged a complaint in the case as the crime allegedly occurred on its premises. However, the investigators did not register the complaint because the firm did not have all the necessary documents.
He said the gems trader and the firm had taken out insurance against theft valued at 10 million baht.