The government armed forces in Syria Thursday reportedly entered Palmyra, the city captured by the Islamic State group. The troops have carried out an offensive against ISIS in an attempt to retake the ancient city, captured by the extremist group in May last year.

The Syrian forces jhave reached the "heart" of Palmyra, Reuters reported, citing the state-run Ikhbariya news channel.

The Syrian Observatory for Human Rights (SOHR) had Wednesday said the troops reached a few km close to Palmyra.

ISIS had asked around 15,000 civilians in Palmyra to flee after the Syrian regime forces neared the city, Agence France-Presse quoted the Syrian monitor as saying. "ISIS called on loudspeakers on civilians still in Palmyra to leave as fighting reached the outskirts of the city," the SOHR said.

At least 70,000 residents were there in Palmyra when ISIS captured it, following which majority of them left the city, according to SOHR director Rami Abdel Rahman.

"The vast majority had already fled — only those too poor to flee stayed behind," he said.