KUALA LUMPUR (BERNAMA) - The 20-year-old safe in the private residence of former prime minister Datuk Seri Najib Tun Razak in Taman Duta, which was finally opened late Friday (May 18) night, contains a small amount of old notes in foreign currency, among other things.

A spokesman for Mr Najib, in a statement late Friday night, said it also contained several documents including the marriage certificate of Mr Najib and Datin Seri Rosmah Mansor.

"It is a steel safe that is over 20 years old and was forcibly opened by locksmiths as the key had gone missing," he said.

Earlier reports quoting police sources had said the safe - which Datuk Seri Najib claimed had not been opened for the past two decades - contained "a lot of cash".

The spokesman said the steel safe at the Seri Perdana official residence in Putrajaya was, however, part of the house.

"There should not have been any problem opening it," said the statement.

Prior to this, the police had reportedly encountered difficulties in opening the steel safe at Mr Najib's private residence at Taman Duta after it was said that the key had long been lost.

The search at the former prime minister's private residence as well as five other locations is part of police investigation into 1Malaysia Development Berhad (1MDB).