Story highlights State media reports 277 detainees in Homs have been released

At least 178 people are killed across Syria on Saturday, opposition activists say

Videos show people running toward explosion-rocked areas and pulling out bodies

The U.N. envoy on Syria will meet with Arab leaders on Sunday

Warplanes crossed the skies over key battleground areas in another bloody day in Syria. Here are the latest developments in the 18-month crisis:

On the ground: Fire from the air

The Syrian military bombarded Aleppo and Damascus provinces Saturday, the opposition Local Coordination Committees (LCC) of Syria said.

Across the country, at least 178 people were killed Saturday -- 89 of them in Aleppo alone -- said the LCC, a network of opposition activists. Fifteen were "summarily executed" in Douma and nine were executed in Hirak in Daraa province, according to the group.

Amateur videos showed people running towards the scene of explosions in Aleppo and pulling out bodies from the rubble.

The LCC said government forces were taking aim at water supply lines but state media denied that accusation.

State-run media said Syrian armed forces had killed "a big number of terrorist mercenaries" in the Deir al-Asafir area near Damascus and arrested many of their leaders. From the beginning, President Bashar al-Assad has refused to acknowledge the popular uprising and blamed the bloodshed as the work of armed thugs.

The region: Rockets land in Iraq

Four rockets fired from Syria landed across the Iraqi border in the town of al-Qaim, Iraqi Interior Ministry officials said Saturday. The rockets fell on a residential area, killing a 4-year-old girl.

A ministry statement said although Iraq has remained neutral in the Syrian conflict, it was ready to respond in the event of another such attack.

Syria has been accused before of staging attacks in Iraq. After the U.S.-led invasion that toppled Saddam Hussein, the U.S. military routinely blamed Sunni insurgents and foreign fighters from Syria for inciting violence in Iraq.

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Al-Qaim is home to a Syrian refugee center. About 4,000 people have crossed into Iraq from the Albu Kamal area of eastern Syria.

In and out of Syrian prisons: State media reports 277 inmates released

The state-run SANA news agency reported Saturday that "277 persons who were misled into getting involved in the recent events" have been released from detention in Homs.

All those freed have "hands (that) are clean of the Syrians' blood," according to the SANA report. Several "turned themselves in after realizing the scope of the conspiracy targeting Syria in implementation of foreign agendas," the state news agency said.

They returned to their homes intent on moving "on with their lives to help build their society."

This is one of several recent mass releases of detainees, according to SANA. On August 27, 332 people on Damascus, 38 in Homs and 20 in Hama who weren't accused of "committing murder" were freed "after pledging to not carry arms again."

World response: Humanitarian help

In Cyprus, just a few miles west by sea from Syria, European Union foreign ministers concluded talks on the growing humanitarian crisis in Syria.

Without a United Nations Security Council mandate to take stronger international action, the world community must continue all it call to support a a political solution, said EU Foreign Policy Chief Catherine Ashton.

She said it was crucial to support U.N. and Arab League envoy Lakhdar Brahimi.

"He's been given a critical role at a very, very difficult time," Ashton told reporters Saturday.

Brahimi is expected to arrive to Cairo on Sunday to hold talks with Arab officials, according to Egypt's state-run MENA news agency.

Ashton announced an extra $64 million from the European Union to help neighboring nations cope with Syrians streaming across the border to flee the war. The money will provide food, water, sanitation, shelter and medical care for the displaced.

U.S. politics: Sen. McCain urges more action

U.S. Sen. John McCain blasted President Barack Obama for not doing more to back the Syrian opposition, calling his administration's actions thus far "shameful."

Speaking to CNN on Saturday from the Ambrosetti Forum along Lake Como in northern Italy, the Arizona Republican specified three steps that he thought the United States could and should take to help those trying to defeat the Syrian regime. These include giving "moral support," getting opposition fighters weapons "so it's a fair fight" and establishing a "sanctuary or free zone" from which the opposition can operate. He said he is not asking that U.S. troops be sent into Syria to battle government forces.

McCain, the ranking member of the U.S. Senate Armed Services Committee who has been a persistent advocate for more action in Syria, claims that a lack of international action to date has contributed to the "rise of extremists, rise of al Qaeda, (and a) greater threat of chemical weapons."

"We've sat still and watched this massacre go on now (with) over 20,000 people (killed)," he said. "How many have to die before we act?"

Demonstrations: Rallies held to support the "children of Syria"

Marches were scheduled Saturday around the United States to bring attention to the Syrian conflict, heighten pressure for action against that nation's government, and raise money for young people affected by the conflict, the event's organizer said.

Nineteen marches were planned from the Boston Common in Massachusetts to San Francisco's Golden Gate Park on Saturday, with more than 5,000 people registering in advance to participate in the marches, the organizer said.

Those taking part are being asked to raise or donate money, which will go toward UNICEF, the United Nations' agency focused on helping children in need.

"The walk (is) a nationwide event to raise awareness about the humanitarian catastrophe in Syria and generate vital funds for children suffering under the dictatorship of Syria's Bashar al-Assad," the organizer, the Syrian American Council, said on a website set up to promote the event. "His regime has launched a brutal crackdown for 16 months to suppress an uprising for freedom, dignity and democracy."