Soon after, he started receiving calls from members of the local Thai community - many expressing the same disbelief, others crying.
"The King is like the father of the nation, we feel like we will be lost without him," Manoonpong added.
Plum Sawaluk, 21, an international student, teared up when asked about her thoughts on the King.
"I feel like I have lost a family member, like my own father has died," she said.
A Thai palace statement said the king died peacefully at 3.52pm on Thursday local time at Siriraj Hospital.
"Even though the doctors tried their best to save His Majesty, his condition deteriorated," it said.
At the Watyarnprateep Temple in Auckland this evening, members of the local Thai community will be gathering for prayers.
A Buddhist funeral rite, or bathing ceremony, will be conducted at the temple at around the same time as when the king's body leaves Siriraj Hospital at 1pm Bangkok time for the Temple of the Emerald Buddha in a procession.
Thais around the world have been asked to refrain from festivities for the next 30 days and to wear black for a year.
Prime Minister John Key has extended New Zealand's sincerest condolences to Queen Sirikit, the Thai royal family and the people of Thailand.
"During his reign, New Zealand and Thailand developed a close and friendly relationship, built on a shared desire for peace and security in our region," Key said.
"King Bhumibol and Queen Sirikit helped to cement the relationship when they visited New Zealand in August 1962."
The Prime Minister said with the strong bond of friendship between the two countries, many would share the deep sense of loss and sadness being felt by the Thai people.
Thai Consul-General in Auckland, Mike Whale, also expressed his condolences to the Thai community here.
"I know this will be a very sad time for Thais everywhere, and also for the many, many other people of the world whose lives His Majesty touched," he said.
A condolences book will be opened at the Consulate-General on Shortland St, central Auckland between 10am and 4pm next week.
Crown Prince Maha Vajiralongkorn, who was educated in Europe and Australia, is expected to succeed his late father.
King Bhumibol is survived by his wife Queen Sirikit, 84, and his three daughters Princess Ubol Ratana, Princess Maha Chakri Sirindhorn and Princess Chulabhorn Walailak.