Deputy Prime Minister Teo Chee Hean said on Friday the police will spare no effort in investigating Wednesday's double murder case in Kovan.

In a statement, the Coordinating Minister for National Security and Minister for Home Affairs said: "The suspected murder case that took place at Kovan is shocking. My sympathies go out to the family of the deceased.

"This is a very serious case and CP (Commissioner of Police) has been updating me regularly. I have asked the Police to spare no effort to make sure that justice is served."

The suspect behind the murders is still at large, and reports on Friday said he is a man in his 50s.