Anthony Artusa was travelling on the City Loop train through Melbourne on Metro Trains when he apparently sat down on a seat with what he estimated were 20 needles sticking out.
In a tweet, Mr Artusa said: "Word of warning when travelling on @metrotrains. Had a lovely surprise this morning when I sat on a seat with around 20 needles sticking out of it. #NeedlesofMelbourne
Victoria Police and Metro Trains responded to the tweet, stating they were interested in hearing more, and now the train company has said they are looking into it.
"This is a terrible act of vandalism and we are thankful that no one was injured. Metro has launched a full investigation into the incident and will work closely with Victoria Police," reports The Age.
Other users on the social media site also expressed their disgust.
"Nefarious act. Thank you for highlighting," said one person, while another said they were always concerned about needles in train seats and brushed their hand over the seats to check.
It follows widespread panic last year when strawberries across the ditch were found to have had needles placed in them. Several copycat contaminations were also found, and as a result much of the fruit had to be put to waste.
A Queensland farm worker was later charged in connection to the strawberry scare.