Sanaa, Yemen (CNN) -- For at least the fourth day in a row, clashes broke out between pro- and anti-government protesters in Yemen's capital Monday morning.
About 200 anti-government protesters were rallying outside Sanaa University calling for regime change as they have since the weekend, when about 300 counter-demonstrators carrying pictures of President Ali Abdullah Saleh confronted them.
The anti-government protesters included at least 150 members of a lawyers' syndicate, who were marching through the streets on their own shouting anti-government and anti-corruption chants, before meeting up with students from Sanaa University.
The two sides threw rocks at each other, and later brandished daggers and knives. Eyewitnesses said the pro-government demonstrators had the weapons, while the anti-government demonstrators were armed with sticks.
Some security forces at the scene tried to separate the two sides, while others stood on the sidelines.
The anti-government protesters accused the counter-protesters of being plainclothes policemen, a charge denied by a government spokesman.
Several protesters were arrested by security forces, said human rights activist Abdulrahman Barman.
CNN employees were told to leave the scene for security reasons as a crush of protesters was pushing up against the gates of Sanaa University, trying to flee the pro-government protesters. More and more security forces came out and were attempting to clear the crowd.
Witnesses reported later that most people had left and the scene was becoming calmer.
On Sunday, hundreds of anti-government protesters marched toward a presidential palace.
Some of them chanted, "First Mubarak, now Ali," referring to the Yemeni president and Hosni Mubarak, who recently resigned as president of Egypt after nearly 30 years in power.
Security forces put up a barbed wire barricade and blocked the protesters' paths about two miles from the palace. At that point, the situation intensified as protesters turned away and attempted to reach the palace through side streets.
According to Tawakkol Karman, a prominent Yemeni rights activist and president of Women Journalists Without Chains, anti-riot police then "went into the crowd of protesters with batons and Tasers," attempting to disperse them.
Karman said she and other protesters were hit with sticks and that at least 12 people were arrested.
One of those arrested, human rights lawyer Khaled Al-Anesi, has since been released.
The CNN crew at the scene was surrounded by security officers, who seized the journalists' videotapes. The tapes were returned on Monday.
Nearby, a group of about 40 pro-government demonstrators chanted, "With our souls, with our blood, we will sacrifice for Ali."
The anti-government group first gathered at the gates of Sanaa University earlier Sunday, where another group of pro-government demonstrators carried pictures of Ali.
Police tried to disperse the crowds and stepped in to prevent pro-government demonstrators from following when the anti-government group headed away from the university and toward the palace.
The group of anti-government protesters included students and rights activists. Their numbers swelled from about 400 to more than 1,000 as they marched through Sanaa's streets.
The anti-government protests were significant because earlier in the day, Yemen's Embassy in Washington confirmed that the opposition coalition had announced its intention to hold a national dialogue with the administration.
The government welcomed the opposition's willingness to initiate a dialogue -- though the protesters indicated otherwise.
Meanwhile, the state-run news agency Saba reported that Saleh had decided to delay a visit to the United States that was to take place in late February.
Saleh has ruled Yemen for 32 years and has pledged not to stand for re-election when his current term -- which started in 2006 -- ends in 2013.
Mubarak's lengthy rule ended Friday when he stepped down after 18 days of anti-government protests rocked Egypt.
Echoes of Egypt's revolution resonated across the region, with anti-government protests in Yemen and Algeria.
Demonstrations were also planned in Iran and Bahrain on Monday.
Brief clashes erupted Saturday in Yemen between hundreds of pro- and anti-government demonstrators who staged rival rallies in the capital.
The clashes, which left a small number of people injured, followed an anti-government protest Friday night in which men armed with knives attacked more than a thousand demonstrators, according to human rights groups.