Iranian security forces on Monday stepped up a crackdown in the Kurdish-populated regions of western Iran that killed a dozen people in a 24-hour period by firing directly at protesters and using heavy weapons, rights groups said.

The Kurdish-populated provinces of western and northwestern Iran have become centers of protest since the September death of 22-year-old Kurdish woman Mahsa Amini, who was arrested by morality police in Tehran.

According to rights groups, anti-regime demonstrations have been particularly violent in several cities in recent days, largely sparked by the funerals of people believed to have been killed by security forces during previous protests.

The Norway-based Hengaw rights group said Iranian forces shelled the towns of Piranshahr, Marivan and Javanroud overnight from Sunday to Monday and posted videos of the sound of live gunfire and what appeared to be the bang of heavy weapons.

In a harrowing video, which Hengaw said was from Javanroud, locals were seen struggling to remove a body from the road under a hail of gunfire.

In the last 24 hours, 13 people have been killed by security forces in the region, including seven in Javanroud, four in Piranshahr and two others elsewhere.

Among six people killed by security forces gunfire on Sunday was 16-year-old Karwan Ghader Shokri, Hengaw said. Another man was killed when security forces fired on the crowd as the teenager’s body was being taken to the mosque, she added.

AFP could not verify the toll immediately.

Internet monitor NetBlocks tweeted Monday that there had been “major disruption” to internet services during the fresh protests, with “mobile internet cut off for many users.”

Hengaw said amid “intense confrontations” between protesters and security forces in Javanroud, there was now a shortage of blood for the wounded in his hospitals.

The New York-based Center for Human Rights in Iran (CHRI) described what happened in Javanroud as a “massacre” with “incessant gunfire, images of bloodied people being carried to safety.”

The impact of the protests was felt in Qatar, where the Iran national team played their first game against England. Iranian players did not sing their national anthem and instead stood stone-faced in support of demonstrations at home.

The latest violence has been coupled with ongoing concerns over the situation in Mahabad, where human rights groups said security forces had sent reinforcements the day before to speed up a crackdown.

“Very concerned that the Iranian authorities are reportedly escalating violence against protesters, particularly in the city of Mahabad,” US Secretary of State Antony Blinken wrote on Twitter.

Hengaw released footage of heavily armed security forces in vehicles driving from the city of Sanandaj toward Mahabad and the nearby city of Bukan.

The Norway-based Iran Human Rights (IHR) Group also released footage showing security forces using live fire against protesters in Piranshahr.

It also showed the distraught mother of Shokri, the teenager killed on Sunday, prostrating on his body as it was brought to the funeral.

“Mother, don’t cry. We will take revenge,” the mourners chanted in Kurdish, the rights group said.

IHR director Mahmood Amiry-Moghaddam released a video showing wounded protesters lying on the street in Javanroud, surrounded by constant gunfire.

“They escalate violence against defenseless citizens,” he wrote on Twitter.

Also in Kermanshah, a Kurdish-populated provincial capital, people took to the streets and chanted “Death to (Supreme Leader Ayatollah Ali) Khamenei,” according to another video posted by IHR.

Iranian security forces have killed at least 378 people since the protests began, a figure told IHR on Saturday.

The demonstrations sparked by Amini’s death have become the most serious challenge to the Iranian regime since the 1979 revolution.

Analysts have noted that violence by security forces has simply sparked more protests, with large crowds turning out for funerals and 40-day “Chehelom” mourning ceremonies.

Kurds form one of the main non-Persian ethnic minority groups in Iran and generally adhere to Sunni Islam rather than the Shi’ism that is prevalent in the country.

In the southeastern province of Sistan-Baluchistan, a police officer was killed and another wounded on Monday when “criminals” fired from a car in a village in Zahedan, the province’s police chief General Mohammad Ghanbari told Fars news agency.

Iran also renewed cross-border rocket and drone strikes against Kurdish opposition groups, which it accuses of fueling the protests, overnight through Monday in neighboring Iraq.

The latest Iranian attacks also came a day after Turkey launched airstrikes against banned Kurdish fighters in Iraqi Kurdistan and northern Syria.