Nineteen Syrian government soldiers and security officers were killed on Monday when rebels detonated explosives in a tunnel under their positions in the northern city of Aleppo, a monitoring group said.

Rebels also launched some 300 shells on the divided city's government-held western sector, killing at least five people and wounding 80 others, the Syrian Observatory for Human Rights said.

Rebels in Aleppo and nearby areas have repeatedly destroyed government positions by tunnelling underneath them to lay explosives. Some such attacks have caused dozens of casualties.

The violence comes after government forces all but surrounded rebel-held eastern Aleppo on Thursday, effectively imposing a siege on the estimated 250,000 to 300,000 residents remaining there.

Some 33 people were killed in government airstrikes in the Aleppo region and neighbouring Idlib province, the Observatory said.

In the village of Abian, west of Aleppo, 11 children were among 16 people killed in a government air raid late Saturday.

In Tramaneen village in Idlib province 14 people were killed in an airstrike, among them three rescue volunteers and an activist, the Observatory said. Three more were killed in the Idlib village of Ahsem.

Aleppo, Syria's largest city before the war, has been divided since fighting erupted for control of the city in mid 2012.

The rebel-held western sector has been devastated by repeated shelling and air raids, often hitting civilian targets including hospitals.

On Thursday government forces cut off the Castello Road, the last route into the rebel-held east. There has been heavy fighting in the area since then as rebels attempt to recapture the road.

Syrian state media said that their troops managed to foil a wide-scale rebel counter-attack on Sunday.

According to the Observatory, almost 800 civilians have been killed since tit-for-tat shelling and airstrikes by rebels and government forces intensified in late April.

Of those, 444 were killed in government airstrikes and shelling on eastern Aleppo, and 325 in rebel shelling of the government-held western sector.

Another 23 died in rebel shelling on the Kurdish-held Sheikh Maqsoud district, while six were killed by Kurdish snipers on or around the Castello Road, which passes close to Sheikh Maqsoud.

The Syrian conflict, which began with peaceful protests against the regime of President Bashar al-Assad, has turned into a four-way war between the government, mainly Islamist rebels, the Islamic State extremist group and leftist Kurdish forces.

Some 4.8 million Syrians have fled the country since 2011, with another 6.6 million displaced inside its borders, according to the latest UN estimates.

Latest news

Syrian opposition rules out future role for President al-Assad

The Syrian opposition said Friday it would not accept any role for President Bashar al-Assad in the future of the war-torn country, reacting to a recent US shift saying that removing al-Assad is no longer a priority for Washington.

Russian Army integrates breakaway forces of Georgian province

Parts of the small fighting forces of the Georgian breakaway province of South Ossetia have been placed under Russian military control, Russian Defence Minister Sergei Shoigu said on Friday.

Czech Republic's Pilsner Urquell beer is now Japanese

Japanese brewing company Asahi completed its takeover of the Czech brewery Pilsner Urquell on Friday, Asahi said in a statement.

Judge approves 25-million-dollar settlement of Trump University case

A US district judge on Friday approved a 25-million-dollar settlement of lawsuits and state fraud allegations against Trump University, the US president's now-defunct business venture.

Former Thai premier Thaksin to junta on reconciliation: 'Cut me out'

Former Thai prime minister Thaksin Shinawatra on Friday announced that he is not interested in the junta-led reconciliation process, three days after the junta handed him a half-a-billion-dollar tax bill for his past business deal.

Dalic: We welcome possible deal between Agrokor and banks

The government welcomes the possibility of an agreement being concluded between the Agrokor food company and creditor banks, and the bill on vitally important companies is not a fallback plan but the result of the government's care for the overall economic and financial stability of Croatia, Deputy Prime Minister and Minister of Economy Martina Dalic told a press conference in Zagreb on Friday.

Croatia, China sign action plan for cooperation in agriculture

The Croatian and Chinese ministries of agriculture on Friday signed an action plan for cooperation in the field of agriculture for the period 2017-2018, the Croatian ministry said in a statement.

ZSE indices up, Agrokor shares in focus of investor interest

The Zagreb Stock Exchange (ZSE) indices on Friday rose by more than 1.8%, with stocks of the Agrokor food and retail concern being in the focus of investor interest again.

Berlin police defend handling of Berlin market attacker

Berlin police defended themselves on Friday against accusations that they stopped surveillance on Berlin Christmas market attacker despite knowing in June 2016 he was dangerous.

Croatia, creditors tailor emergency measures to save tottering giant

Croatia's tottering retail and food giant Agrokor reached an agreement with its creditors, putting its debts standby and allowing it to continue working during emergency restructuring, the Croatian branch of Austria's Erste Bank said Friday.

Agrokor's creditors say standstill agreement to go into force today

A standstill agreement regarding the Agrokor concern's existing financial obligations to banks will take effect on Friday, additional capital will be injected into the concern in the coming days and the concern will be actively restructured, which includes a change of its management, it was said on Friday after a meeting between Agrokor's suppliers and creditor banks.

Palestinians, UN slam Israel's new settlement plan

Palestinians, Israeli activists and the UN lambasted the government of Israeli Prime Minister Benjamin Netanyahu on Friday, a day after it gave the go-ahead for the first new West Bank settlement in a quarter of a century.

South Sudan rebels release three abducted foreign oil workers

South Sudanese rebels have released three foreign engineers they abducted in early March in the oil-rich Upper Nile region, Foreign Affairs Ministry official Mawein Makol Arik said on Friday.

Turkish opposition: Imprisoned party chief has gone on hunger strike

The head of Turkey's pro-Kurdish opposition party has launched a hunger strike from prison.

European leagues threaten Champions League schedule clashes

The European Professional Football Leagues (EPFL) on Friday threatened schedule clashes on Champions League matchdays in an ongoing dispute with the governing body UEFA.

Danish court revokes citizenship of IS volunteer

A Danish appellate court on Friday stripped a man of his Danish citizenship for volunteering to fight for the extremist Islamic State in Syria.

Banks and Agrokor agree on key elements of standstill agreement

Member banks of the coordinating committee of financial creditors and representatives of the Agrokor food company have in principle agreed on key elements of a standstill agreement, which is expected to be signed later today, announcing changes in the company's management team, Erste Bank said in a statement on Friday afternoon.

Syrian man on trial in Sweden; mosque attack labelled terrorism

A Syrian man went on trial Friday in the southern Swedish city of Malmo, charged with terrorism and arson after an attack last year on a building used as an assembly hall by Shiite Muslims.