An influential Sudanese imam had to be removed from a mosque in the capital, Khartoum, after the worshipers confronted him with not leading protests against embattled President Omar al-Bashir.
In a video released on social media, a man named Imam Abdul Hai Yusuf, who often supports the government, screams, "Get up and lead us out of this mosque!"
A desperate crowd then calls "only decline [of the regime]".
The police fired tear gas at demonstrators marching on Friday prayers.
After three weeks of demonstrations, 22 people have died throughout the country.
The protests, initially against the rising cost of fuel and bread, have turned into a call for Mr. Bashir to end his 30-year rule.
What happened on Friday?
A video shared on Facebook seems to show a member of the Khatim al-Mursaleen Mosque, acting against Mr. Yusuf, a Saudi educated imam.
Mr. Yusuf, known for encouraging his followers to march in solidarity. With Gaza or Syria, he had to be beaten out of a door near the pulpit.
Previously, he had called on the government to exercise restraint in the current unrest.
Another video shows crowds chanting in front of the mosque.
The authenticity of the videos could not be checked immediately.
The protests on Friday in Khartoum and near Omdurman seemed to attract more people than before and were more widespread, reports Reuters.
The security forces hunted the demonstrators, but there was no immediate prosecution report on victims.
Why are people protesting?
Demonstrations began on December 1
The protests have escalated into a broader demand for an end to the reign of President Bashir, who came to power in 1989 after a coup. Activists accuse him of bad management of the economy.
Over the past year, the cost of some goods has more than doubled, while the Sudanese pound has more than doubled in value.
Three quarters of Sudan's oil revenues were lost after the southern half of the country voted in favor of secession in 2011, leading to the formation of South Sudan.
His economy has also been burdened by over 20 years of US economic sanctions, which were lifted in October 2017. The US had introduced economic sanctions after accusing Sudan of sponsoring terrorist groups.
Mr. Bashir's regime has been charged with widespread human rights violations.
In 2009 and 2010, the International Criminal Court (ICC) accused him of several charges of genocide, war crimes and crimes against humanity, and a warrant for his arrest was issued.