Hundreds of teachers are protesting across Iran to demand a fair pay, adjustment of pensions, and the release of their detained colleagues.

The protests in dozens of cities follow two days of sit-ins in schools where teachers had reportedly gone on strike.

On January 31, teachers staged a protest outside the parliament building in Tehran and in front of Education Ministry offices in other cities, including Shiraz, Isfahan, and Ahvaz, to present their demands.

Last month, Iran's parliament passed legislation to raise teachers' salaries following several days of countrywide protests and a strike that impacted the Islamic republic's education system.

Teachers have staged several protests in recent weeks. Security forces have sometimes responded with heavy-handed tactics and arrested some participants.

Reports say at least five teachers were arrested during the protests on January 31, including three protesters who were detained outside the parliament in the Iranian capital.

"Jailed teachers must be released!" some of the protesters chanted, according to amateur videos posted online, while others accused the parliament of making "false promises."

Measures passed by legislators on December 15 guarantee teachers will earn about 80 percent of the salaries of university faculty members -- one of the protesters' demands.

The protesters have also urged the government to move more quickly on a planned grading system for teachers based on experience and performance. They also want their pensions to be aligned with the salaries of working teachers as soon as possible.

A statement released by the protesting teachers on January 31 said that the situations of retired teachers as well as those who are employed have reached a crisis point.

The statement also accused the parliament of acting "in the interests of the government," while noting that the judiciary silences all dissenting voices instead of supporting "the legitimate demands" of the teachers.

The protests come amid soaring inflation as the impact of crippling U.S. sanctions and years of mismanagement hit the country hard.

Many teachers have complained that they struggle to make ends meet.

The New York-based Center for Human Rights In Iran said last month that dozens of teachers' rights activists have been jailed "on manufactured charges that reflect the criminalization in Iran of dissent, peaceful protests and assembly, and independent labor activism."