Kabul, Sep 13 (IANS): At least five people were killed and 23 injured early Friday morning as two car bombs and ensuing firing hit the US consulate in Herat city in western Afghanistan, a local security source said.

"Four or five armed militants, carrying heavy weapons and suicide vests stormed the consulate building at around 0515 local time," the security source said

"They initially detonated two car bombs and tried to enter the facility and take control of the building. Sporadic firing still could be heard later Friday morning there," he added, Xinhua reported.

The Taliban have claimed the responsibility for the incident.

Taliban spokesman Zabiullha Mujahid told the local media that the militants launched the attack and five Taliban fighters were involved in it.

The security source said no member of the consulate was injured in the incident.

"All US diplomats are safe in the building," the source said.

The killed included one Afghan civilian, two attackers and two local security guards.

Of the civilians who were passing by, 18 were injured. Two guards and three policemen were also wounded in the incident in the city, which is the capital of Herat province and located 640 km west of Kabul.

"The number of the casualties might go up," the source said.

The blast also damaged the consulate compound wall and several other nearby houses. Local TV channels showed the gate and supportive walls of the facility were destroyed by the force of the blasts.

The explosions sent a thick black smoke above the site.

The Taliban-led insurgency has been rampant since the militant group launched annual offensive in April against Afghan government forces and about 98,000 NATO-led troops stationed in the country.

The Taliban asked civilians to stay away from official gatherings, military convoys and centres regarded as the legitimate targets by militants, not to support the government and foreign troops.