On Monday students in several universities in Tehran and Isfahan held rallies and chanted slogans against the Basij militia and the clerical regime for a third day.

In a video showing a rally at Isfahan Industrial University students chant: "Execution and imprisonment no longer scare us" and "Get lost Basiji".

Referring to the many highly-educated passengers who were killed in the Ukrainian airline downed by an IRGC missile on Wednesday last week, the protesting students at Sharif Industrial University in Tehran were chanting slogans against clerics ruling the country.

The United States warned Iran against firing at protesters. The State Department spokesperson Morgan Ortagus told Radio Farda Washington is watching how the Islamic Republic conducts itself in the face of popular protests.

"We want the regime to know that the United States is watching, that the world is watching, and that we are going to shine a very, very big light on any abuse by the regime to their own people. We are not going to tolerate killing innocent protesters. [U.S. President Donald] President Trump was very clear about that over the weekend," Ortagus said on January 13.

"The Iranian people have been lied to by their own government for at least three or four days before they finally admitted, before they were caught red-handed and had to admit that they were actually responsible for the downing of the Ukrainian airliner."

Protest at Isfahan's Industrial University on January 13.

According to some reports, security and intelligence agents were calling hundreds of students in Isfahan Sunday evening and threatening them not to continue the protests.

According to social media users, dozens of protesters were arrested on Sunday in various cities including Tehran, Babol, Kermanshah, Amol and Tabriz where 10 students were arrested on Sunday but were freed later.

For a second day in a row, thousands of protesters chanted slogans Sunday against the Iranian Supreme Leader Ali Khamenei and the Revolutionary Guard in Tehran and several other Iranian. Riot police fired tear gas at protesters in many places including a few underground stations in Tehran.

Protesters' slogans on Sunday were markedly aimed at Khamenei and the Revolutionary Guard which under international pressure had to accept responsibility for downing the Ukrainian airliner but blamed it on "human error".

On Sunday students at Beheshti University refused to stampede on U.S. and Israeli flags, while booing a handful of students belonging to Basij militia who stepped on the flags.

Protest at Tehran's Sharif Industrial University on January 13

In a tweet Monday afternoon Internet watchdog Netblocks said a drop in internet connectivity was registered at Sharif University in Tehran from 11:50 UTC where students have been protesting, but national connectivity remains stable despite sporadic disruptions on third day of #Iran protests. Some Iranian social media users have also reported loss of mobile internet connection.

The protests in Tehran started Saturday evening following a vigil held at Amir Kabir University for the 176 victims of the Ukrainian passenger jet including dozens of students and academics on their way to Canada via Ukraine. The vigil soon turned into anti-government demonstrations demanding regime change.

Since Saturday demonstrators have also rallied in several other cities including Mashhad, Kermanshah, Tabriz, Rasht, Isfahan, Shiraz, Qazvin, Ahwaz, Yazd, Shiraz, Semnan and Amol.

The Ukrainian plane was targeted a few hours after Iran's missile attack on two bases in Iraq and only after three days of international and domestic pressure the Revolutionary Guard accepted the responsibility for downing the plane.

It appears that the protest demonstrations that shook Iran in mid-November are making a comeback with a renewed rigor. However, the riot police appear to be more reserved after reportedly killing up to 1,500 demonstrators in the previous round of the protests. No deaths were reported so far on Saturday and Sunday.