Across the Middle East and North Africa, CNN's reporters and iReporters are covering protests, many of them inspired by revolts in Tunisia and Egypt that toppled those countries' longtime rulers. Check out our interactive map explaining the roots of the unrest in each country and full coverage of the situation in Libya. Have a story to tell from the scene? Click here to send an iReport. CNN's Fareed Zakaria breaks down what the movements toward democracy mean.

Developments on unrest in the Middle East and North Africa:

[LIBYA 9:06 p.m. ET, 4:06 a.m. local] Egypt's new prime minister, Essam Sharaf, appeared before thousands of protesters at Cairo's Tahrir Square on Friday, telling them he is "of the people" and would resign if he failed to meet their demands. Sharaf, Egypt's former transportation minister, was sworn in Friday after the resignation of Ahmed Shafik, the last prime minister appointed by Hosni Mubarak.

[LIBYA 6:00 p.m. ET, 1:00 a.m. local] The United Nations said Friday it is studying Libya's request to install a more loyal diplomat as its ambassador. A letter from Libya's government asked that former Foreign Minister Ali Abdussalam Treki be approved as its envoy. Treki, who recently served as the president of the U.N. General Assembly, would replace Mohamed Shalgham as ambassador in New York.

[LIBYA 2:16 p.m. ET, 9:16 p.m. local] Libyan government spokesman Majid al-Dursi told CNN that "Zawiya has been captured, Zawiya has been liberated."

Battalions of forces loyal to Moammar Gadhafi attacked protesters with mortars and machine guns as they were demonstrating in the city's Martyrs Square, eyewitnesses said. The troops also assaulted an ambulance and killed people who fell wounded.

"Civilians were killed but we can not say how many. We buried nine people so far," the witness said. "The attack was indescribable. Direct gunfire was opened on people."

[SAUDI ARABIA, 12:04 p.m. ET, 8:04 p.m. local] A second protest unfolded in Riyadh after Friday prayer, according to two Saudi activists who requested they not be identified because of concerns for their safety.

As many as 40 anti-government demonstrators gathered outside Al-Rajhi Mosque for a short protest. At least one man involved in organizing the protest was arrested, the activists said.

The activists said the protesters attracted a crowd of worshipers leaving the mosque. Some of the protesters carried signs showing a map of Saudi Arabia that did not contain the words "Kingdom of Saudi Arabia," an affront to the Saudi royal family.

[LIBYA, 11:56 a.m. ET, 6:56 p.m. local] A witness said the Friday attack in Zawiya was an "indescribable" and deadly assault. The witness said forces loyal to Moammar Gadhafi attacked peaceful protesters in Zawiya with mortars and machine guns.

[LIBYA, 11:32 a.m. ET, 6:32 p.m. local] A C-130 cargo plane labeled with a U.S. flag landed in Tunisia, Libya, on Friday, CNN has learned.  Secretary of State Hillary Clinton stated Friday that two C-130 planes were en route to Tunisia to help with the humanitarian crisis in Libya.

[LIBYA, 11:02 a.m. ET, 6:02 p.m. local] At least 15 people have been killed and 200 wounded in the Libyan city of Zawiya, according to a doctor, who said "there is a river of blood" at the hospital where the injured are being treated.

Earlier, a report from Libyan State TV said that people in Zawiya, west of Tripoli, and "their public leadership have secured and took control over the city from the 'armed terrorist elements.'"

The doctor said wounded people started arriving at the hospital Friday morning, and most of the injuries are from gunshots.

Many of the injuries are critical, with wounds in the head and chest, the doctor said. The hospital is running out of medical supplies and "the situation is very bad," the doctor said.

[LIBYA, 7:47 a.m. ET, 2:47 p.m. local] Pro-Gadhafi forces have clashed with opposition fighters in Ras Lanuf, opposition sources in eastern Libya told CNN Friday.

[SAUDI ARABIA, 6:36 a.m. ET, 2:36 p.m. local] Demonstrators protested in Saudi Arabia's Eastern Province on Friday to demand the release of Shiite prisoners they feel are being held unjustly.

An outspoken Shiite prayer leader who demonstrators say was arrested last Friday was a focal point of the "day of rage" protest, said Ibrahim Al-Mugaiteeb, president of the Human Rights First Society.

Sheikh Tawfeeq Al-Amer was arrested Friday after a sermon stating that Saudi Arabia should become a constitutional monarchy, Al-Mugaiteeb said.

[YEMEN, 6:26 a.m. ET, 2:26 p.m. local] Security forces opened fire on protesters on the northern Yemeni city of Harf Sufyan Friday, killing two people and injuring nine others.

[IRAQ, 6:10 a.m. ET, 2:10 p.m. local] Authorities imposed curfews and limited access to city centers across Iraq as thousands of protesters demanded economic progress and an end to corruption, police said. Demonstrators were reported to be gathering in Baghdad, Basra, Nineveh, Anbar and Salaheddin.

The developments follow weeks of demonstrations across the country by protesters angry about unemployment, poor basic services, corruption and a lack of freedom. At least 13 people died in protests on February 25.

[LIBYA, 4:43 a.m. ET, 11:43 a.m. local] The eastern Libyan town of al-Brega was calm early Friday, witnesses said, a day after forces loyal to Moammar Gadhafi launched airstrikes on the oil port in an effort to reclaim it from the opposition.

[LIBYA, 1:59 a.m. ET, 8:59 a.m. local] Venezuela's president says embattled Libyan leader Moammar Gadhafi was receptive to the idea of an international commission coming to the North African country when the two heads of state spoke this week.

"I consulted with him. I asked him if he was willing to accept a commission of countries," Chavez said in remarks broadcast on state-run VTV Thursday night.

"And he told me, 'Look, Chavez, not only of countries; I hope the whole United Nations come here to see the reality of what's happening before they start condemning the Libyan government or the Libyan people, before they start thinking as they are now, and preparing to invade Libya."

[LIBYA, 11:03 p.m. ET, 6:03 a.m. local] Venezuelan President Hugo Chavez said Thursday that embattled Libyan  leader Moammar Gadhafi agreed with Chavez's proposal to send a goodwill commission to Libya when the two leaders spoke Tuesday.

In remarks broadcast on state-run VTV, Chavez did not specify whether such a commission would actually go to Libya.