SANA via Associated Press
In this photo released by the Syrian official news agency SANA, Syrian President Bashar Assad, right, meets with Alaeddin Boroujerdi, Chairman of the Committee for Foreign Policy and National Security at the Iranian Shura Council, in Damascus, Syria, Thursday, Aug 4, 2016. Boroujerdi said operation by the Syrian government and allied forces in Aleppo aims to "liberate" tens of thousands of residents from the grip of what he called terrorist groups.

BEIRUT — Syrian rebels and insurgents said on Friday they are edging closer to breaking the government force's siege of the opposition-held part of Aleppo, taking parts of the city's military college close to a strategic siege area.

The announcement from two ultraconservative factions, including al-Qaida's branch in Syria which is now known as the Levant Conquest Front, came on social media, saying they had pushed into the college, where artillery men trained in peace-time. The facility is located about 1.6 kilometers (1 mile) from the besieged opposition areas.

The Britain-based Syrian Observatory for Human Rights monitoring group confirmed that a part of the facility was captured. The activist group said fierce clashes had erupted around the college, with casualties on both sides.

The media office of Hezbollah, the Lebanese Shiite militant group fighting alongside Syrian President Bashar Assad's forces, denied reports of a rebel advance.

The rebels on Friday also shelled a nearby, government-controlled neighborhood of Aleppo, killing at least three civilians, according to the Observatory. Syrian state media said five civilians, including three children, were killed.

The U.N. estimates that between 250,000 and 300,000 residents have been trapped in the besieged, eastern part of Aleppo since pro-government forces cut the last supply route in July. The world body and numerous relief organizations have warned of a looming humanitarian catastrophe as conditions deteriorate.

Russia, a staunch Assad ally, had declared it was offering humanitarian corridors for residents to leave the area, but rights groups said such passages are not neutral and don't offer guarantees to civilians wishing to use them.

Also Friday, Denmark's armed forces announced their aircraft have for the first time dropped bombs in Syria's Raqqa province, where the Islamic State group has its self-declared capital.

Defense Command Denmark said the F-16 raid happened "in the past week" but did not give further details. The supreme military command said the Danish fighter jets also participated in operations over Iraqi provinces targeting IS command and control facilities, weapons stocks and fighters.

The Scandinavian country joined the international coalition fighting the Islamic State group in October 2014. Danish warplanes have previously participated in airstrikes on IS forces in Iraq, but not Syria. Those planes were brought back for repairs last year.

Denmark's present contribution to the anti-IS effort includes seven F-16 fighter jets, among others, with a mandate to bomb in Syria.

Associated Press writer Jan Olsen in Copenhagen, Denmark, contributed to this report.