UPDATE 1-Kazakh oil workers ask who ordered firing at protesters

* Protesters ask who gave police orders to fire

* Prosecutor-general rejects "rumours" of bigger death toll

* Government, metals giants swear loyalty to Nazarbayev

AKTAU, Kazakhstan, Dec 20 (Reuters) - Sacked oil workers in Kazakhstan took to the streets on Tuesday demanding to know who ordered police to fire on protesters during clashes over the past days that killed at least 15 people in the worst violence in the Central Asian state in decades.

About 100 demonstrators confronted dozens of riot police in Aktau, capital of the western, oil-producing Mangistau region where protests in two nearby towns have turned into bloody clashes.

The clashes have not spread beyond the region, but political analysts say the protests suggest that broader public pressure is mounting for President Nursultan Nazarbayev to relax the authoritarian system he has built up since Soviet times.

"We demand to know: Who gave the order to shoot at oil workers?" said Nurzhan Imangaliyev, 27, who was laid off by oil company Karazhanbasmunai (KBM) in May after he and thousands of others joined a strike to demand higher wages.

"Why did our relatives die as a result of a peaceful, social argument?"

On the first working day after a long weekend, the rally was smaller than those held during the four-day public holiday, when about 500 protesters had gathered daily in Aktau's central Concord Square.

Many of the protesters took shelter from biting wind against the walls of a Soviet-era apartment block under a poster of Kazakhstan's futuristic new capital Astana, a prestige project for Nazarbayev, a former member of the Soviet Communist Politburo who has run Kazakhstan for more than two decades.

At least 14 people were killed in clashes between oil workers and police in the oil town of Zhanaozen on Dec. 16, the 20th anniversary of Kazakhstan's independence from Moscow. Another one was killed in the nearby village of Shetpe on Dec. 17.

"Independence Day was perhaps more about celebrating Nazarbayev's legacy rather than gaining independence from Russia," Lilit Gevorgyan, analyst at HIS Global Insight, said.

"Through carefully orchestrated, lavish ceremonies, Nazarbayev wanted to showcase his success as a political leader, but instead the deadly clashes showed the unpleasant side of his rule."

"HOOLIGANS"

The Kazakh authorities have said police only opened fire after being attacked by "criminal elements" or "hooligans" who were threatening civilians.

Kazakh Interior Minister Kalmukhanbet Kasymov told a government meeting on Tuesday that 110 people had been wounded in the clashes, including 17 police officers.

Many oilmen protesting in Aktau said they did not trust official information on the casualties and believed the death toll to be significantly higher.

The authorities denied this. "Once again, we want to stress that rumours about some mass bloodshed are absolutely unfounded, misleading and provocative," Nurdaulet Suindikov, spokesman for the Kazakh prosecutor-general's office, told a news briefing on Tuesday.

Nazarbayev, who says that maintaining stability in the multinational country is his main priority, has blamed the clashes and looting on what he said were criminals who torched private homes, official buildings, shops and banks, as well as cars and buses, and plundered ATM cash-machines.

Prime Minister Karim Masimov told a cabinet meeting: "I believe it's just the time for us to close ranks around our head of state, and demonstrate the might and stability of our country."

A 71-year-old former steelworker who has ruled with an iron fist for more than two decades, Nazarbayev has imposed a state of emergency in Zhanaozen until Jan. 5. Movement is limited in and outside the town, and a curfew is in force.

"The situation in the cities of Zhanaozen, Aktau and the village of Shetpe, as well as in general in the region, is stable and under the control of law-enforcement bodies," Kazakhstan's prosecutor-general's office said on Tuesday.

JOB OFFERS

London-listed Kazakh mining giant ENRC said on Tuesday that more than 17,000 of its workers were holding rallies in support of Nazarbayev in four of the country's regions.

ENRC said in a statement that its rallies had been prompted by a similar action taken by ArcelorMittal, which owns the country's only major steel plant in Temirtau, where Nazarbayev started his working career.

Deputy Prime Minister Umirzak Shukeyev, heading a government commission on the Zhanaozen events, told the cabinet that sacked oilmen would be offered jobs at mining companies. He promised that they would be paid 80-90 percent of their previous wages, and that the government would pay relocation grants.

Some oilmen could be given jobs in servicing units of oil firms, he added.

Despite the small number of protesters in Aktau, the daily rallies signal that a pocket of dissent has developed.

Nazarbayev enjoys sweeping powers and brooks no opposition. One of his aides said this week there was no risk of an "Arab-style revolution" because Kazakhs supported the president.

In Aktau, not everyone agrees.

"Oil is slavery. Here, there is no democracy," said one of Aktau's protesters, Baurzhan, a sacked oil worker from oil firm KBM, jointly owned by London-listed KazMunaiGas Exploration Production and CITIC, China's biggest state investment company.

Another laid-off oil worker, a father of four who declined to give his name, said: "They say hooligans did this, but if you hadn't been paid for seven months then you would think about raiding an ATM. The oil workers have mouths to feed."