KABUL, April 22 (Xinhua) -- Four civilians and an assailant were killed and at least 15 people wounded after a suicide bomb blast ripped through a main road in western neighborhood of Kabul, capital of Afghanistan on Sunday, reported local media 1 TV television.

"The blast occurred in front of a local school where a voter registration site is located in Qala-e-Nazir area of Dashti Barchi locality," the report said.

Several people were near buildings for registering to get voting cards before the blast.

The attacker was killed on the spot after the explosion which occurred roughly at 10:10 a.m. local time.

Security forces have cordoned off the area for precautionary measures and the injured were shifted by ambulances to nearby hospitals.

On April 1, the Afghan Independent Election Commission (IEC) announced Oct. 20 as the date for the upcoming parliamentary polls, which has been delayed for a couple of times over the past years.

First parliamentary election in the post-Taliban Afghanistan was held in 2005 while the second parliamentary polls took place in 2010.

However, the 2015 parliamentary polls, originally set to be held in early 2015 following presidential elections, were repeatedly delayed.