BEIRUT, Lebanon –Syria’s army has launched a fierce assault on rebel fighters in a bid to break their year-long siege on Aleppo’s central prison, a monitor, state media and activists reported Wednesday.

The rebels and their allies from the Al-Qaeda-affiliated Al-Nusra Front have been trying to overrun the jail, which remains in government control, to release political prisoners reportedly held in very poor conditions.

“The army, the (pro-regime) National Defense Forces militia, Arab fighters and Lebanon’s Hezbollah are in fierce combat against jihadists from Al-Nusra Front and Islamist rebels in the Sheikh Najjar industrial area, one kilometer (0.6 miles) from Aleppo’s central prison,” said the Syrian Observatory for Human Rights.

Troops loyal to President Bashar al-Assad had broken through on the road leading to the prison, said Observatory director Rami Abdel Rahman, adding that ending the siege “would constitute a strategic victory for the regime.”

State news agency SANA said, meanwhile, that “the army has taken over the village of Hilan, and is advancing towards other areas that surround Aleppo prison.”

An activist in Aleppo, Mohammad Wissam, gave AFP a similar account.

“The regime wants to reach the prison. (Troops) have not managed to do so yet, but if they do… they can then reach the Castelo road, which links Aleppo’s liberated (rebel-held) areas to the northern countryside,” he said.

Rebels in Aleppo city, once Syria’s commercial capital, rely on supply routes leading to the countryside as a rear base.

The northern countryside of Aleppo borders Turkey, a key supporter of Syria’s revolt and home to hundreds of thousands of refugees fleeing the country’s violence.

On Wednesday, near Aleppo prison, rebels blew up the Al-Kindi hospital, which the loyalist army had used as a position before its takeover by the opposition.

“The building is very big, and it could be used by regime troops (should they reclaim it) to monitor supply routes used by the revolutionaries,” Wissam told AFP via the Internet.

“Everyone is afraid the regime might besiege (rebel areas of) Aleppo,” he added.

Elsewhere in Syria, four Kurdish fighters and seven pro-regime militiamen were killed in fighting in the majority Kurdish province of Hasakeh, said the Observatory.

And in the eastern province of Deir Ezzor, four Islamist fighters were killed in an overnight battle against the radical Islamic State of Iraq and the Levant.

Activists and the Observatory say ISIL has recently launched a fresh bid to set up an Islamic state under its control along the Syrian border with Iraq.