KABUL, Afghanistan — Roadside bombs killed at least five civilians and wounded seven others on Friday in Afghanistan, provincial officials said, while the Islamic state group claimed responsibility for the killing of a policewoman a day earlier.

Omer Zwak, spokesman for the provincial governor in southern Helmand province, said the five killed were travelling by car near Lashkar Gah, the capital of the province. The death toll may rise, he added.

In a separate roadside bomb attack in western Herat province, seven women travelling in a minivan were wounded, the provincial governor's office said.

No one immediately claimed responsibility for the attacks, but Afghanistan has seen a nationwide spike in bombings, targeted killings, and violence on the battlefield as peace negotiations in Qatar between the Taliban and the Afghan government have stalled.

Meanwhile, in a statement late Thursday, the Islamic State group claimed responsibility for the killing of a policewoman in eastern Nangarhar province earlier that day. The statement said that she was working with the "apostate" Afghan security services.