Tens of thousands of Iraqis have taken to the streets in a Sunni-dominated western province, the latest in a series of demonstrations against the country's Shi'ite-led government.

The protesters blockaded a main highway Friday in Anbar province west of the capital, Baghdad, holding placards and chanting slogans against the government of Prime Minister Nouri al-Maliki.

Protests were also reported in the northern Sunni towns of Tikrit, Mosul and Samarra.

Many accuse the government of trying to marginalize and deprive the rights of Sunni Muslims, a religious minority in the predominantly Shi'ite country.

Prime Minister Maliki on Friday called the protests “unacceptable.” He said in a speech that protesters should rely on “civil means of expression” and not block roads or engage in activity that encourages sectarianism.

Long-standing tensions between the two groups were inflamed last week following the arrest of 10 bodyguards assigned to Finance Minister Rafia al-Issawi, one of the country's top Sunni officials. Many Sunnis saw the arrests as politically motivated.

Protesters have for days held large demonstrations and blockaded main roads in Anbar province, saying they will not back down until the government meets a series of demands, including releasing Sunni prisoners and changing terrorism laws.

The tension has threatened to plunge war-torn Iraq back into sectarian chaos, just a year after the last U.S. troops left the country.