AMMAN, Jordan -- Hundreds of Jordanians chanted slogans against the king and threw stones at riot police as they protested in several cities for a second day Wednesday amid rising anger over fuel price hikes.

Jordan, a key U.S. ally, has so far weathered nearly two years of Arab unrest that has seen longtime rulers toppled in Egypt, Libya, Yemen and Tunisia. The kingdom has seen nearly two years of street protests calling for political reforms, but they have largely been peaceful and rarely targeted King Abdullah II himself.

Tensions rose late Tuesday after the government announced it was raising prices for cooking and heating gas by 54 per cent to reduce a massive budget deficit and secure a $2 billion loan from the International Monetary Fund.

About 2,000 protesters pelted downtown shops with rocks in the southern city of Karak, shattering windows and forcing owners to close, according to a witness, Mohammad Matarneh, a 38-year-old shopkeeper.

"Down, down with you, Abdullah," they chanted. "Get out and leave us alone."

The chants were a rare show of criticism aimed at Jordan's Western-oriented monarch, who has the final say on all civic matters and has implemented a series of political reforms in a bid to stave off the unrest that has been sweeping the Middle East for two years. Public criticism of the king carries a three-year prison term.

Protesters also burned tires to block main roads and pelted riot police with stones in at least eight other cities across Jordan on Wednesday, including Naour, a city near Amman where 500 angry youths torched a car and threw rocks at police and passers-by, two police officials said on condition of anonymity because they were not allowed to make press statements. And around 200 protesters attacked a police station in the northwestern city of Theiban, breaking its windows, the officials said.

The rioting was set off by Prime Minister Abdullah Ensour's announcement Tuesday night on state TV that fuel subsidies would be lifted in a bid to offset $5 billion in state losses from a rising fuel bill. The price of a gas cylinder jumped from 6.50 Jordanian dinars ($9.18) to 10 dinars ($14.12).

Police spokesman Mohammad Khatib said 24 protesters accused of attacking riot police in Tuesday's skirmishes were arrested in Amman. At least 14 people were injured, including 10 police who were hit by rocks, according to a police statement.

Police also reported $1.4 million in damages, including smashed shop windows, burned police cars and other vehicles and damage to government offices. The statement also said a courthouse in Mazar and three gas stations in other cities were torched.

No injuries were immediately reported in Wednesday's demonstrations.

The Muslim Brotherhood, Jordan's largest opposition group, called for a massive rally late Wednesday joining Arab nationalists, Marxist and Communist groups, youth movements and professionals. It said the protest would be held in a main Amman city square, housing the interior ministry and other vital government offices and Western hotels.

The site hosted Jordan's largest protest of 2,000 activists late Tuesday. Police sealed it off to traffic Wednesday but were allowing people to enter on foot.

Meanwhile, the U.S. Embassy issued a warden message, advising Americans in Jordan to be vigilant, exercise caution and avoid potential flashpoint areas.

The 50-year-old king has been fighting to fend off a host of domestic challenges, including a Muslim Brotherhood boycott of parliamentary elections, increasing opposition from his traditional Bedouin allies and an inability to keep the Syrian civil war from spilling over the border.

So far, Abdullah has largely maintained control, partly by relinquishing some of his powers to parliament and amending the country's 60-year-old constitution. His Western-trained security forces have been able to keep protests from getting out of hand. And most in the opposition remain loyal to the king, pressing for reforms but not his removal.

The stakes are high: Abdullah is a close friend of the United States and has been at the forefront in its global war on terrorism, including in Afghanistan. Jordan serves as a buffer zone to Saudi Arabia, another Sunni Muslim country, and to Israel, a friend under a peace treaty signed in 1994. The kingdom hosts the largest Palestinian population outside the West Bank.

The Jordanian teacher's union, meanwhile, called on members to strike, although it only affected public schools and it was unclear how many teachers stayed home.

Fahd Abol-Haj, who owns a dry cleaning laundry in the eastern city of Russeifeh, said his 8-year-old son went to school but found no teachers.

"So, he returned home," Abol-Haj said.