In an update today, the Ministry of Defence (Mindef) said Corporal First Class (NS) Pang's condition is now critical and he is in the intensive care unit.
His surgery was completed on Tuesday. It was his third.
Pang's manager and co-founder of NoonTalk Media Dasmond Koh said in an Instagram post in Chinese that although Pang's second operation was a success, his condition deteriorated after a few hours, the Strait Times.
This meant that he had to go through another round of surgery.
"Everyone is waiting for Aloysius' condition to improve... He will get better," Koh wrote.
Pang had been due to start shooting a romantic drama My One In A Million next month after Chinese New Year, but Mediacorp said that the role will now be recast to allow him to focus on his recovery.
Pang started kicked off his acting career at the age of 9 and took a break when he was 14. He returned to acting when he was 22 years old.
Pang's mother arrived in New Zealand and spoke with him in the hospital and his father and brother were due to arrive Monday.
Singapore has a policy of mandatory conscription of young men into the armed forces, police force or civil defense force. Most serve full time for two years, followed by annual training obligations.
The ministry described Pang as an "Operationally Ready National Serviceman" indicating that he had completed his full-time service. It described him as an armament technician and his rank as corporal first class.
Pang's Singapore-based agency, NoonTalk Media, wrote on Facebook that it was waiting for more information on the actor's condition from the military and his family.
"Please bear with us and join us in praying for his swift recovery," the agency wrote.
New Zealand's defense force said a member of Singapore's military was injured during a live-firing exercise that New Zealand's military hosts each year.
Singapore's defense ministry said it was investigating the incident to determine the cause.
Pang is known for his work on the movie "Young & Fabulous" (2016) as well as television series that include "The Truth Seekers" (2016) and "C.L.I.F." (2011).
- AP