BEIRUT — Syrian rebels on Monday captured four villages in the heartland of President Bashar Assad's minority Alawite sect as they fought government troops for the second straight day in the mountains overlooking the country's Mediterranean coast.

Opposition fighters also said they captured about 400 villagers and pro-government gunmen in battles in the area.

Alawites, an offshoot of Shiite Islam, dominate Assad's regime. The capture of the villages in the coastal Latakia province was a symbolic blow to Assad, whose forces have been taking territory in recent weeks in central Syria.

Syria's conflict has taken on an increasingly sectarian tone in the last year, pitting predominantly Sunni Muslim rebels against members of Assad's Alawite minority.

The Britain-based Syrian Observatory for Human Rights said rebels captured the villages after attacking government outposts in the Jabal al-Akrad hills on Sunday. The group, which relies on reports from activists on the ground, said at least 32 government troops and militiamen and at least 19 rebels, including foreign fighters, died in Sunday's fighting.

Much of Latakia has been under the firm control of Assad's forces since the beginning of the conflict more than two years ago, but some areas, including Jabal al-Akrad, are close to rebel-held areas and have seen fighting.

It was a rare success for the rebels on the battlefield in recent weeks. Assad's forces have been on the offensive since taking the central town of Qusair in June, and last week captured a key district in the central city of Homs, an opposition stronghold.

A rebel in Latakia, who identified himself as Mohammed Haffawi, told The Associated Press that the rebels were getting closer to the town of Haffa, which was captured by Assad's forces in June last year, and had killed dozens in the fighting.

Haffawi said the rebels captured about 400 Alawite villagers and pro-government gunmen on Monday.

"They are in a safe place now and under the protection of the Free Syrian Army," he said, referring to key rebel group.

A Syrian activist also said the rebels had captured about 400 Alawites. He spoke on condition of anonymity for fear of government reprisals.

Meanwhile, Syria's state-run news agency SANA said government troops forced rebels out of three villages in Latakia that they had stormed earlier. It wasn't clear which villages the report was referring to but SANA said government troops had "killed dozens of terrorists, including Libyans and Tunisians."

Syria main's opposition bloc, the Western-backed Syrian National Coalition, hailed the rebel advance and said that Assad's troops had used the villages to attack rebel-held civilian areas.

The SNC also charged that regime forces used toxic gas in a chemical weapons attack in the Damascus suburb of Adra on Monday and urged the international community to investigate the attack. The opposition has claimed more than a dozen such attacks across Syria and the latest purported attack could not be independently confirmed.

Last week, the United Nations said chemical weapons experts would depart "within days" for Syria to investigate three specific allegations of chemical weapons use. The U.N. gave a green light for the investigation following an "understanding" reached between the Syrian government and a delegation from the world organization that visited Damascus last month.

At the site of one of the regime's victories in Homs, Syrian Defense Minister Gen. Fahd Jassem al-Freij toured the ravaged district of Khaldiyeh on Monday, praising troops for what he told state TV was a "military miracle."

Standing in front of the historic Khalid bin al-Waleed mosque in Khaldiyeh, al-Freij vowed the army will "triumph against this universally-backed terrorism which is being exported to us."

Also Monday, rebels pressed on with their battle for the Mannagh military air base near the border with Turkey that they have been trying to capture for about a year. Syrian army warplanes carried out air raids to help troops defending the air base, activists said.

More than 100,000 people have been killed since Syria's conflict started in March 2011 as largely peaceful protests against Assad's rule. After opposition supporters took up arms to fight a brutal government crackdown on dissent, it turned into an armed uprising and later escalated into a civil war.

The Assad government claims it is not facing a popular revolt, but a conspiracy by Gulf Arab states and the West seeking to destroy Syria by supplying Islamic extremists with weapons and funds.

Also Monday, Human Rights Watch said ballistic missiles fired by the Syrian army into populated areas have killed hundreds of civilians in recent months.

The U.S.-based group said it has investigated nine apparent missile attacks that killed at least 215 people, half of them children, between February and July. The most recent attack HRW investigated occurred in the northern province of Aleppo on July 26, killing at least 33 civilians including 17 children.

HRW activists visited the sites of seven of the nine attacks and found no apparent military targets nearby, the group said. Ole Solvang, a senior researcher with HRW, said it's impossible to distinguish between civilians and fighters when firing missiles with wide-ranging destructive effects into densely populated areas.

The HRW called on Assad to stop indiscriminate attacks. Government officials could not immediately be reached for comment.