KANO, NIGERIA — Hundreds of Nigerian soldiers descended Wednesday on a city in the country's north where a state governor had to be evacuated by helicopter after protesting youths went on a deadly rampage, attacking his residence and setting an election commission office on fire.
The chaos erupted in the capital of Niger state, Minna, prompting authorities there to declare a statewide 24-hour curfew.
The unrest comes as Nigerians across the country take part in demonstrations this week following the government's decision to end a popular gas-subsidy program that kept fuel prices cheap for more than two decades.
Tens of thousands - who joined the strike under the slogan of "Occupy Nigeria" - have protested across the country since a national strike started Monday. Anger over the government's action has spurred violence in a nation already facing uneasy religious and ethnic divisions.
At least 10 people have been killed, officials said.
Young people set the local electoral commission office in Minna on fire Wednesday, killing a police inspector who was guarding the building.
Nigeria's government has warned that a paralyzing national strike risks "anarchy" in the oil-rich nation.
In Lagos, Nigeria's commercial capital of 15 million people, several hundred protesters on Wednesday took over a major highway leading to the islands where the wealthy live.
One protester carried a sign that read, "We are ready for the civil war."
"We can sleep on the road until daybreak. We are not tired," said Godwin Bassey, 16. "We voted for them. They need to obey our voice."
In a statement, Attorney General Mohammed Bello Adoke described the strike by major labor unions as illegal. He warned public employees that the government would implement a "no-work, no-pay" policy for those who join the strike.
However, public workers sometimes go weeks without pay in Nigeria, where corruption and mismanagement have plagued government for decades.
"Continuing disregard of that order is [dangerous] to the public interest, as it constitutes an open invitation to anarchy," Mr. Adoke said in a statement issued late Tuesday.
The nationwide strike came after President Goodluck Jonathan removed subsidies on Jan. 1 that had kept gasoline prices low. Prices at the pump more than doubled overnight to at least $3.50 per gallon from $1.70. The costs of food and transportation also doubled in a nation where most live on less than $2 a day.
Mr. Jonathan insists the move was necessary to save the country an estimated $8 billion a year, which he promises will go toward badly needed road construction and other public projects.
Protesters, however, say the time has come to end government corruption in a nation where military rulers and politicians have stolen billions.
Already the strike has exposed ethnic and religious divisions. An angry mob attacked a mosque and a Muslim school on Tuesday, killing at least five people in the country's largely Christian south, the Nigerian Red Cross said.
Unrest could affect oil production in Nigeria, which pumps about 2.4 million barrels of oil a day and is a top crude supplier to the United States. Yet most oil fields remain unmanned and offshore oil fields provide much of its capacity.
Babatunde Ogun, president of one major union representing oil workers, said Wednesday his group planned to escalate its strike.
"It means in the short term, there will be no export of [natural] gas. There will be no power," Mr. Ogun said. "Everything will be at a standstill."
The strike has closed Lagos' busy Apapa Port, cutting off cargo shipments.
Businesses remain shuttered, while air carriers canceled more international flights. Organizers say the strike will continue until the government restores the subsidies.