Series of blasts shocked Herat city the capital of Herat province 640 km west of Afghan capital Kabul on Monday leaving over 30 people dead or injured.

"So far, we have received four dead and 27 injured including police and civilians," a doctor in Herat hospital Barakatullah Mohammadi told Xinhua.

Meantime, gun fight continues between attackers and security forces, police said.

Four blasts have shocked Herat city since beginning attack on security forces at around noon time.

NATO helicopters are flying over the area to control the situation.

A group of attackers with some of them suicide bombers occupied a building next to the NATO-led Provincial Reconstruction Team (PRT) at around 11:50 a.m. local time and begun targeting the compound.

The attackers first detonated a car bomb next to the PRT office and then stormed the building, according to police.

Xinhua's reporter at the site said that immediately after the attacks Afghan police and army personnel have rushed to the area.

Officials said that a press release would be sent to media after completion of investigation.