Websites were swamped Monday with postings attacking Chinese and other foreigners in the city-state after it was reported that a 52-year-old local cabbie had died of his injuries following Saturday's pre-dawn accident.
The crash instantly killed the 31-year-old Ferrari driver, Ma Chi, while the taxi passenger, a 41-year-old Japanese woman, died in hospital two hours later, a police spokeswoman told AFP.
Police gave no other details but local media said the Ferrari driver was a financial adviser from Sichuan who was applying for permanent residency and already living in a Singapore penthouse with his family.
Disgruntled locals seized on the incident as another reason to attack the government's immigration policies and the presence of more than a million foreign workers and professionals in the crowded city-state.
Foreigners are blamed for pushing up living costs, straining public transport and stealing jobs, with mainland Chinese bearing the brunt of attacks.
The Straits Times newspaper said the Ferrari was a limited-edition model that Ma had bought for Sg$1.8 million ($1.43 million) for his 30th birthday last year.
Pictures from a video of the accident published in local newspapers showed Ma's car apparently ramming the taxi after he allegedly ran a red light following a night out with friends.
Hundreds of indignant comments were posted online.
"I hate to drag nationality into this tragedy but the stupidity of a single (Chinese) possibly drunkard driver has caused such catastrophic damage to so many people," Tan Wee Meng posted on Facebook.
Singapore's population grew from 4.4 million in 2006 to 5.2 million in 2011, largely the result of a higher intake of immigrants as well as guest workers and professionals.
The accident came two months after a Malaysian cleaner at Singapore's Changi Airport was killed after he was hit by a taxi hijacked by a Chinese guest worker.
The government's more open immigration policy was a hot issue during the general elections in May 2011 in which the ruling People's Action Party garnered an all-time low of 60 percent of the vote.