Updated

Jordanian authorities will strike those who incite violence during protests with an "iron fist," the country's police chief said Thursday as the Islamist-led opposition vowed to continue demonstrations that have rattled the U.S.-allied kingdom.

The protests, which erupted Tuesday across Jordan in response to the government's hiking fuel and gas prices, are the largest and most sustained to hit the country since the start of uprisings in the region nearly two years ago.

Gunmen taking advantage of street chaos caused by the protests fired on two police stations late Wednesday, wounding 17 people, including 13 police officers, officials said. One of the assailants was killed in the ensuing firefight.

"We will hit with an iron fist those who violated the law by stirring unrest," said Gen. Hussein Majali, adding that he had "zero tolerance" for such actions.

Since Tuesday, 157 protesters — including two Syrian refugees — were arrested for street violence, Majali said. The Syrians confessed to have been paid by an unidentified Jordanian political party to join protests to beef up crowd numbers, he added.

Other "outlaws" with police records took advantage of the disorder to rob banks and homes and carry out carjackings, he said. Assaults on power and police stations and a tourist bus also occurred, and in one incident Wednesday, gunmen hurled a hand grenade at a government office.

One Jordanian protester was killed and 71 others — including 54 policemen — were wounded in 100 violent riots in the past two days, he said.

On Thursday, a national holiday for Islamic New Year, only six protests took place nationwide, a police statement said. In the southern town of Tafila, four policemen were wounded when a handful of gunmen among the 150 protesters fired at them as they stood outside the governor's office.

The demonstrations also spread to the largest of Jordan's 13 camps that host Palestinian refugees, a population which had refrained from protests since the outset of the so-called Arab Spring uprisings. In Baqaa, just outside Amman, residents and police said some 400 young Palestinians pelted riot police with stones and burned tires to block streets, prompting riot police to fire tear gas.

Jordan hosts 2 million Palestinian refugees and their descendants displaced in the 1967 Arab-Israeli war.

Jamil Abu-Bakr, a leader from the Muslim Brotherhood — which is spearheading the opposition to the price hikes and the ruling system in general — said his group will continue staging street protests until the government's decision is revoked. He said the next demonstration is scheduled for Friday in Amman and a general strike is planned for Sunday.

The opposition, which also includes Arab nationalists, communists and the largely secular Hirak movement of mostly young Jordanians, has seized on popular anger over the government's decision Tuesday to raise prices for cooking and heating gas by 54 percent in a bid to woo more of the population into its camp.

The government has defended the price hikes, saying they are necessary to reduce a massive budget deficit, part of Jordan's efforts to secure a badly needed $2 billion loan from the International Monetary Fund to shore up the kingdom's shaky finances.

Jordan has been hit by frequent, but small, anti-government protests over the past 23 months, but these demonstrations have shifted the focus from the government squarely to the king. So far, Abdullah has largely maintained control, partly by relinquishing some of his powers to parliament and amending several laws guaranteeing wider public freedoms.

But his opponents say the reforms are insufficient, and the violent protests Tuesday and Wednesday indicated many in Jordan are growing frustrated with the government's inability to address a host of trouble, including unemployment, rising poverty and inflation.

The government was in contact Thursday with the Brotherhood and other activists to "bring the situation under control because instability in Jordan is in nobody's interest," an official said on condition of anonymity because he was not authorized to brief the media.

But the Brotherhood's political wing said in a statement that three party leaders, including secretary general Hamza Mansour, met with and Jordan's deputy prime minister late Wednesday to discuss the price hikes, but that "no agreement was reached on calming the anger in the street."

Jordanian government officials have accused the Brotherhood of inciting the unrest to score political points ahead of parliamentary elections in January. The fundamentalist group is boycotting the polls over disagreement with the government on an election law that it says favors pro-king loyalists.

On Thursday, youth activists expressed concern with the violent turn the protest had taken, and called for a return to non-violent demonstrations.

Waseem Haddad, a 23-year-old member of the youth Hirak movement, said the street violence "is damaging our peaceful campaign in the past 23 months for real reforms, greater public liberties, justice and equality and better opportunities for the youth."