The man in his 60s died last Tuesday while checking tax returns, but no-one realised he was dead until Thursday.

The head of personnel at the office in the Finnish capital, Helsinki, said the man's closest colleagues had been out at meetings when he died.

He said everyone at the tax office was feeling dreadful - and procedures would have to be reviewed.

An anonymous government official told BBC News Online the man had been working in his own office with the door closed.

"People thought he wanted to work in peace and no-one disturbed him," the official said.

He was found only when a friend called to have lunch with him.

'Coincidences'

According to the Finnish tabloid newspaper Ilta-Sanomat on Monday, co-workers had assumed the dead man - a tax auditor - was silently poring over returns.

"The reason for this was caused by many coincidences," Anita Wickstroem, director at the Helsinki tax office, told AFP news agency.

"He was very much working alone and often visiting companies, while his friends and colleagues who used to have lunch or coffee with him were busy in meetings or outside the office at the time," she added.

There were about 100 other staff in the auditing department on the same floor the dead tax official worked on.