BEIRUT: Combat raged near a historic mosque in the Syrian city of Aleppo on Tuesday while anti-government activists reported fresh clashes near a police academy west of the city.

The fighting near the Umayyad Mosque in the walled Old City of Aleppo threated to further damage the 12th century structure, part of which was burned during clashes last year.

Since July 2012, government forces and rebels seeking to topple President Bashar Assad have been fighting over Aleppo, the country's largest city and a major prize in the civil war. While rebels have gradually expanded their control, fighting has left much of the city, considered one of Syria's most beautiful, in ruins.

The Britain-based Syrian Observatory for Human Rights said Tuesday that rebels clashed with government forces near the Umayyad Mosque amid intense gunfire and explosions.

Syria's state news agency said "terrorists" had detonated explosives near the mosque's south wall, causing "material damages" to the wall and the nearby area. Assad's regime refers to the opposition as "terrorists."

The mosque, also known as the Great Mosque of Aleppo, dates the 12th century and sits near a medieval covered market in Aleppo's walled city, which is a UNESCO World Heritage site. The mosque was heavily damaged in October, 2012, and a fire torched the market the month before.

Also Tuesday, activists reported fresh fighting near the police academy that has become a key government military installation west of the city.

The Observatory said the two sides were shelling each other's positions while the government launched airstrikes in the area.

Video posted online in recent days shows rebel groups firing homemade rockets and mortars at the academy and blasting it with captured tanks. The videos appeared genuine and corresponded with other Associated Press reporting.

The Observatory said the dead in the last two days of fighting in the area included 26 rebel fighters, 40 soldiers and five pro-government militiamen.

The police academy, which activists say the government has turned into a military base, has recently emerged as a new front in the battle for Aleppo, Syria's largest city. Since storming into the city in July, 2012, rebels have slowly expanded their control there while taking over army installations in the northern countryside. Losing the police academy would make it more difficult for the regime to shell opposition areas and support its troops inside the city.

An Aleppo activist who goes by the name Abu al-Hassan said via Skype that rebels coming from Idlib province to the west are now trying to clear the army from residential areas near the academy before they attack it.

"Yesterday and today they have been trying to go forward but there are lots of shelling and airstrikes," he said.

The fighting has largely destroyed Aleppo and caused humanitarian conditions for the city's remaining civilians to plummet.

On Tuesday, Human Rights Watch said more than 141 people had been killed in at least four missile strikes by the Syrian government in and near the city of Aleppo last week. About half of the dead were children, it said.

The New York-based group said the strikes hit residential areas and called them an "escalation of unlawful attacks against Syria's civilian population."

A Human Rights Watch researcher who visited the sites said up to 20 buildings were destroyed in each area hit by a missile. There were no signs of any military targets in the residential districts, located in rebel-held parts of Aleppo and its northern countryside, said Ole Solvang, the researcher.

Syria has never acknowledged the strikes, and portrays the conflict as a foreign conspiracy carried out by "terrorists" to weaken the country.

Also Tuesday, the Observatory said the death toll in a car bomb attack in Damascus had risen to eight. All were regime security officers, it said.

The blast late Monday struck a security checkpoint in the neighborhood of Qaboun, less than a kilometer (mile) from Abbasid Square, northeast of downtown. It was followed by several other smaller blasts thought to be mortar shells landing in various districts of the capital.

The explosions and subsequent gunfire caused panic among residents who hid in their apartments.

Syria's state news agency said the blast was caused by a suicide car bomber and caused an unspecified number of casualties.

The U.N. says some 70,000 have been killed since Syria's conflict began in March 2011.