Supporters of Chiam left the SDP .
Supporters of Chiam formed the Singapore People 's Party ( SPP ) in 1994 , with former SDP member Sin Kek Tong as its pro-tem leader .
Supporters of Chiam left the SDP and formed the Singapore People 's Party ( SPP ) in 1994 , with former SDP member Sin Kek Tong as its pro-tem leader .