Dimitrios was in the suburb of Kilbirne around 9.30pm last night when he needed to make a stop at a Westpac external ATM facility.
When he pulled up outside the branch, he and his partner noticed a brown substance all over the glass doors and walls.
But it was when he got out of his car that he was overwhelmed with a nasty stench.
"I needed to deposit some money into the ATM machine and as me and my partner drove by she made a comment saying someone had spread mud all over the doors.
"I got out of the car to complete my transaction and even from the sidewalk about 10 metres from the door I knew straight away from the stench that it wasn't mud."
The brown substance had also been smeared all over the ATM screen, keyboard and even the card swipe where bank members need to slide their card to open the doors.
Dimitrios told the Herald the smell was revolting and he feels awful for staff members and cleaners who had to deal with the mess in the morning.
"I got a bit closer and then saw that they had spread [poo] all over the external ATM machine screen and keypad, I walked up to the door where the writing is and was just going use the internal ATM machine, but the grub somehow managed to spread it in the slot where the card slides through to open said door.
"They smeared their own faecal matter on literally everything. It stunk to high heaven.
"I feel for the person who has to clean that up."
Westpac confirmed the incident and assured customers the facility has been cleaned and the interior was not impacted.
"We are aware of an incident outside our Kilbirnie branch on Sunday night," a spokesperson for Westpac told the Herald.
"The facility has been cleaned thoroughly. The branch interior was not affected and we are open for customers.
"We are working with police to investigate the incident."
