A mystery pooper dubbed the 'brown bomber' has struck an Invercargill pool complex for a sixth Friday in a row.

Swimming teacher in pool with child. Source: 1 NEWS

Splash Palace Aquatic Centre manager Pete Thompson told Fairfax Media that a "smidgeon" of poo was found in the leisure pool at about 4.30pm.

It is the sixth week in a row that pool staff have had to call a 'code brown'.

"The mode is dissimilar to anything else we have had. It was a very tiny 10 cent piece-size which suggests it probably came out of a baby's togs," Thompson said.

Splash Palace staff had been on the lookout for the 'brown bomber' after finding deposits in the pool five weeks in a row.

However, the man, woman or child behind today's incident still managed to elude them.