NEW YORK • A security guard has been arrested for stealing US$5 million (S$7 million) in diamonds from a New York jeweller after a construction worker accidentally threw the precious stones into the trash, police said.

Wilfred Martinez was charged with the theft after police said he was caught on surveillance video from inside J. Birnbach, a jewellery maker located in the heart of New York's diamond district.

Mr Jonathan Birnbach had told the police last week that he kept the diamonds inside three wooden boxes in an unlocked safe for easier access, and did not notice that they were missing as he rarely handled them.

Workers renovating the interior of the business threw the boxes out without realising that they contained diamonds, chief of detectives Robert Boyce told a press conference yesterday.

Martinez saw the boxes and took them into the toilet, where he consolidated the diamonds into a single box before leaving with them, Mr Boyce said.

He sold some of the diamonds to another dealer for US$68,000 - a "bargain price", Mr Boyce said.

The guard admitted to the theft in a statement to police after his arrest, and investigators have recovered the stones.

J. Birnbach specialises in high- end diamonds and has created jewellery worn on red carpets from the Oscars film awards to the Emmys television awards, according to its website.

REUTERS