They were detained by Indonesian police on Friday.
The cell planned to launch rockets at Singapore's Marina Bay waterfront where the track is located from Batam Island in Indonesia, 15 miles away. They were reported to be members of Katibah Gigih Rahmat, an Indonesian terror organization with links to the Islamic State.
"MHA (Ministry of Home Affairs) is aware that plans were being made by the six terror suspects arrested by the Indonesian authorities," a spokesperson for Singapore's interior ministry said on August 5.
"Our security agencies have been coordinating closely with the Indonesian authorities since the discovery of this attack plot, to monitor the activities of the group and to apprehend those involved."
The suspects are believed to have coordinated with Bahrun Naim, the alleged mastermind behind a terrorist attack in Jakarta which killed four people in January. The four terrorists who carried out that attack were also killed.
Naim is now believed to be in Syria fighting for the Islamic State.
Next month Prime Minister Lee Hsien Loong will launch the SG Secure movement, according to the International Business Times. The movement aims to make citizens "more security conscious" in response to a "steadily increasing" risk of terrorism.
A statement on the SG Secure website reads, "The community has to take action to counter potential threats in our midst. The community must be vigilant and look out for security threats and know how to respond; needs to be cohesive during peacetime and in the aftermath of a crisis; and to stay resilient and strong should a crisis occur."