Papua New Guinea's prime minister has declared a state of emergency in the country after at least 15 people died in violent riots on Wednesday.

Prime Minister James Marape announced the measure would last for 14 days, with 1,000 defense personnel on standby to react to any escalation in violence.

Violence erupted in the capital, Port Moresby, on Wednesday evening after a group of soldiers, police officers and prison guards launched protests against the government over a pay cut that officials blamed on an administrative glitch.

TV footage showed thousands in the streets of Port Moresby, many carrying what appeared to be looted merchandise, as black smoke billowed over the city.

Within hours, riots had also taken root in the city of Lae, some 300 kilometers (186 miles) to the north.

Marape apologized to the country, saying the bursts of "lawlessness" would "not be tolerated." "This is your country as much as it's my country. Breaking the law does not achieve certain outcomes," he said at a press conference.

Police Commissioner David Manning confirmed at least 15 people were killed during the outbreak of civil unrest.

National Capital District governor Powes Parkop said the unrest represented an "unprecedented level of strife" in Port Moresby, while local newspaper the Post Courier called it the city's "darkest day.".

"What is most important is that we must end this strife," Parkop told a local radio station Wednesday evening.

"Nobody will be a winner in this type of civil unrest."

The burst of violence highlights the often volatile nature of life in Papua New Guinea, a country plagued by poverty and high levels of crime.

Police in the Pacific Islands nation have struggled with a surge in violent crime over the past year.

Perched less than 200 kilometers from Australia's northernmost border, Papua New Guinea is the largest and most populous state in Melanesia. 

(With input from agencies)