UPDATED 8.47pm A man lay dead a Wellington flat for more than a week before neighbours alerted authorities to the strong smell.

A police spokesman said they went to a Housing New Zealand apartment block on Dixon St in central Wellington about 3.30pm today when they found the body of a 78-year-old man in a flat on the third floor.

Neighbours called police complaining of a strong smell coming from the flat.

The spokesman said the man was last seen a couple of weeks ago, but he was unsure how long his body had laid undiscovered.

It was unknown how the man died but it did not appear to be suspicious.

The body is the third previously undetected corpse found in Wellington in just over a year.

The body of 78-year-old Jim Grant was found in an apartment complex in central Wellington in March, after he was thought to have died two months earlier.

Last year Dean Stewart died in his Newtown house and wasn't found for months.