A 34-year-old man was arrested on Friday at 11.30pm in connection with the double murders at Kovan, police said in a statement on Saturday morning.
"The arrest of the suspect was possible through the close collaboration between the Singapore Police Force and the Royal Malaysian Police," the statement read. "The SPF would like to thank the RMP for their unwavering support and assistance in this case."
Mr Tan Boon Sin, 67, was found dead at his home in Hillside Drive on Wednesday. His eldest son, Mr Tan Chee Heong, 42, was found dead about a kilometre away outside Kovan MRT station, after being dragged by a car.
Both men suffered slash wounds to their necks, while the getaway car was found abandoned in Eunos a day later.
More details are expected at a police press conference due later on Saturday.