At least seven people have been killed and 15 others wounded in a suicide bombing in front of a government ministry in the Afghan capital, Kabul, officials said.

The explosion on July 15 happened at the Rural Rehabilitation and Development Ministry, police spokesman Hashmat Stanikzai said.

There were both civilians and security forces were among the casualties, Stanikzai said.

He added that the death toll will likely rise.

Fraidoon Azhand, a spokesman for the ministry, confirmed the attack, saying the bomber struck at a security gate as employees were exiting the compound during rush hour.

Some family members gathered at the scene soon afterward, seeking information about their loved ones.

"I've come here and I'm trying to find my son, I am really worried," said Sayed Ashraf, whose son works at the ministry.

"I went to the hospital but I couldn't find him there and now I am waiting here to find him, I'm trying to reach him on the phone but his phone is switched off," Sayed Ashraf was quoted as saying by Reuters.

The Islamic State (IS) extremist group claimed responsibility for the attack, saying it was carried out by one of its suicide bombers.

On June 11, a suicide bombing in front of the same ministry left 13 people dead and some 30 others wounded.The Islamic State extremist group claimed responsibility for that attack.

Earlier on July 15, the United Nations mission in Afghanistan reported a record number of civilian deaths in the country with a 22 percent jump in civilian casualties from suicide attacks during the first half of the year.

Based on reporting by Reuters and AFP