It was reported that Wong had taken part in a hiking activity with a group at Tambaig Adventure Park in Kg Duvanson, Putatan, earlier today.
He is believed to have suffered a heart attack.
Wong was Sabah DAP chief and a two-term MP for Sandakan. He won the seat in the 2013 general election and retained it in the May 9 polls last year.
In the Dewan Rakyat, a minute of silence was observed in his honour.
Deputy speaker Nga Kor Ming said Wong’s death was a big loss to the country, adding that the Sandakan MP had always contributed to the house.
He also conveyed his condolences to Wong’s family.
Sabah Chief Minister Shafie Apdal, when met at the Queen Elizabeth Hospital here, said he was told by the doctor that Wong was brought in at around 9am after complaining of chest pain.
He said the state had lost a true Sabahan who, as a minister, had always been committed to his work.
“We have lost a friend today, and a fighter. This is the time for us to mourn with his family,” he said.
“Wong was a leader who contributed a lot to the people.”
Meanwhile, DAP veteran Lim Kit Siang said Wong had served the country well.
“He was a dedicated political worker for the well-being and greatness of Malaysia and Sabah, the very embodiment of the example that it is no contradiction to be, at the same time, a great Malaysian and a great Sabahan,” he said in a statement.
DAP secretary-general Lim Guan Eng said Wong believed “passionately” in the party’s agenda for a multiracial and multi-cultural Malaysia “that respects the rule of law, upholds Sabah’s rights, and celebrates diversity”.
In a statement, he added that Wong was a “key witness and player in history for both state and country” through his role in the last general election.