Fighters from the Islamic State of Iraq and the Levant (ISIL) have abducted scores of people, including several Christian families, after seizing a strategically located town in the central Syrian province of Homs, an activist group has said.

The UK-based Syrian Observatory for Human Rights (SOHR) said on Friday that at least 230 people had been kidnapped, including 60 Christians, some of whom were taken from a church in Qaryatain, which was captured overnight after heavy fighting with the Syrian army.

Qaryatain is near a road linking the ancient city of Palmyra to the Qalamoun mountains, along the border with Lebanon.

ISIL started the attack on Wednesday morning when three suicide bombers targeted pro-regime checkpoints at entrances to the city, the observatory said.

"IS[IL] seized Al-Qaryatain town in the southeastern countryside of Homs after violent clashes with pro-regime forces and loyalist fighters," SOHR head Rami Abdel Rahman said.

A total of 37 regime soldiers and loyalist fighters were killed, while 23 ISIL fighters also died, Abdel Rahman said.

Conflict death toll

ISIL has destroyed many churches and Christian shrines in Syria, and demanded that Christians living under its rule pay a tax known as jizya.

The ongoing clashes between government troops and ISIL are one of many fronts in Syria's war, which has left more than 240,000 people dead since it began in March 2011, according to the SOHR.

The latest toll compiled by the observatory showed that 11,964 children were among 71,781 civilians killed in Syria.

At least 88,616 regime forces were killed - or one third of all deaths documented by the SOHR - including 50,570 soldiers and the rest allied fighters.

The conflict began with anti-government protests before spiralling into a multi-front war after a brutal regime crackdown.