DAMASCUS, Syria (AFP) - At least 22 people were killed in mortar fire on Tuesday on Syria's coastal city of Latakia, in one of the bloodiest shellings there since the country's war began, state media reported.

The toll rose to "22 people killed and 62 wounded" in the attack on eastern neighbourhoods of the regime bastion, state television said.

Earlier, state news agency Sana had said 12 people died and 57 were hurt when two mortar rounds struck residential neighbourhoods.

Latakia lies in the heartland of the minority Alawite sect to which Syria's ruling clan belongs and has been largely spared attacks during four and a half years of civil war.

A rare car bombing in September killed 10 people and wounded dozens in Hamam Square in the provincial capital.

Rebels and Islamic militants, including Al-Qaeda's Syria affiliate, have long targeted the region, in part for its symbolic value as a regime stronghold.

According to a Syrian security source, Tuesday's attack took place near Latakia's Tishreen University, "where many students were gathered".

Abir Selman, a 24-year old literature student at the university, said she was waiting for the bus when the mortars struck.

"I saw blood everywhere and people running in every direction," she told AFP.

"I passed by a corpse that had nothing left except for its legs... We wait at this bus stop every day," Selman added.

Syrian state television broadcast video footage of blood-stained streets littered with broken class and mangled cars.

Meanwhile, one person was killed and five wounded in a mortar attack on residential areas of Damascus, state television said.

According to the Syrian Observatory for Human Rights at least 10 mortar rounds struck various neighbourhoods of the capital.

The Britain-based Observatory said another four people, including a child, were killed in government rocket fire on the flashpoint town of Douma, east of Damascus.

The toll was likely to rise as some of those wounded were in critical condition, the monitoring group said.

Douma lies in the opposition bastion of Eastern Ghouta, which is regularly bombarded by regime forces.

Suspected Russian strikes on the town last week killed at least 23 civilians.

More than 250,000 people have been killed in Syria's conflict, which began in March 2011 with anti-government protests but spiralled into a civil war after a brutal crackdown by government security forces.