A state of emergency instituted in a Kazakhstan oil town during a December wave of labor unrest and was allowed to lapse this week.

The emergency decree was lifted Tuesday, five days after President Nursultan Nazarbayev said the crackdown wouldn't be extended because the "situation had taken a normal course."

The violence -- the worst in the oil-rich Central Asian nation since it gained independence from the former Soviet Union in 1991 -- claimed 16 lives as striking oil workers in the city of Zhanaozen clashed with security forces.

Witnesses said police fired indiscriminately on unarmed strikers during the clashes, the BBC reported. A video circulated on YouTube appears to show demonstrators being shot by riot police, though security officials claimed victims were struck by ricochets.

Authorities said three police officers are facing charges related to the violence, while 18 people accused of taking part in the disturbances and looting have been arrested.

Human Rights Watch said it appears Kazakh authorities are trying to silence government critics despite promises of a transparent investigation into the violence.

Protesters loyal to the opposition in Kazakhstan demonstrated in January after Nazarbayev's ruling Nur Otan party won 80 percent of the vote.

The country recently passed a law meant to abolish a single-party rule, though the Organization for Security and Cooperation in Europe said the recent elections fell short of international standards.

U.S. Assistant Secretary of State for South and Central Asian Affairs Robert Blake said in Washington Tuesday that Kazakhstan's promises to reform its political system and uphold human rights remain "largely unmet," Radio Free Europe/Radio Liberty reported.

Blake, speaking at an event to mark the 20th anniversary of Kazakhstan's independence, called for more respect for civil liberties as a way to "institutionalize democracy" in the country and strengthen its ties to the United States.

Kazakh Foreign Minister Yerzhan Kazykhanov said at the event his country "embraces democracy" but is still "learning the ropes," RFE/RL reported.

Since the violence, Nazarbayev has taken steps to make amends for the crackdown in an effort to maintain Kazakhstan's reputation as a bastion of stability in Central Asia.

In addition to the criminal inquiry into the behavior of the security forces, he fired his son-in-law, Timur Kulibayev, as chief of the country's sovereign wealth fund, which party owns the companies whose workers were striking.

The oil strikes came just as Western energy companies such as Exxon were making decisions on long-term investments worth about $154 billion in a massive new Caspian Sea oil field known as Kashagan, The New York Times reported.

Union spokesman Malik Mindigaliyev said that of about 1,300 Zhanaozen workers who went on strike, more than 850 had accepted offers of new employment.

"Every person makes his own choice," he said. "We take the jobs because we have to feed our families."

Kazakh Prime Minister Karim Massimov told the Times oil workers would be given raises of up to several hundred dollars per month while $300 million would be invested in Zhanaozen.

"I strongly believe this issue will be resolved soon and it will not spread to the foreign companies working in Kazakhstan," he said.