The Home Ministry said Tuesday Arifin bin Ali @ John Wong Ah Hung, 48, was now placed on a Restriction Order (RO) under the same Act.
Arifin fled Singapore in December 2001 when the security operation against the local JI network in Singapore was mounted.
He was arrested in Bangkok by the Thai authorities in May 2003 and subsequently deported to Singapore.
While hiding in Thailand, he was involved with a group of people in plotting terrorist attacks against targets in Thailand, the ministry said in a statement.
The ministry also announced that another Singaporean who was a member of the Moro Islamic Liberation Front (MILF) in the Philippines and arrested last April, had also been put under restriction order for two years under the ISA beginning May 6.
Ahmad Jalaluddin Sanawi, 53, had undergone military training at the MILF camp in the Philippines and contributed to fund-raising efforts in support of the MILF cause, the ministry said.
Ahmad left Singapore in December 2001 and had remained in hiding overseas since to evade the Singapore authorities, but he surrendered to the local police in April.
Source: BERNAMA - Singapore Releases JI Member