The members of the Afghan Local Police (ALP) force were on a joint patrol with NATO-led coalition forces near Puli Alam town when the blast was detonated.
"One of the police vehicles hit an IED (improvised explosive device) in which eight local police were killed and their pick-up truck was totally destroyed," Rais Khan Sadeq, Logar provincial deputy police chief, told AFP.
Din Mohammad Darvish, the provincial spokesman, confirmed the incident and the death toll. "Eight local police are killed in a Taliban bomb," he said.
Founded in 2010, the ALP is a controversial unit tasked with community-level policing to suppress violence in some of the country's most dangerous areas.
It was designed as a homegrown force of locals ready to take on Taliban hardliners in places where the national police and army were scarce, but is often criticised as indisciplined and poorly-trained.
The Taliban vowed their annual spring offensive would target international airbases and diplomatic buildings with multiple suicide bombings, as well as featuring "insider attacks" by Afghan soldiers and "special military tactics".
Shah Wali Khan, the head of the High Peace Council in Helmand, was also killed in a similar attack in the province on yesterday.
More than a decade after the Taliban government was ousted in 2001, Afghanistan remains in the grip of a violent insurgency with militants launching daily strikes on government officials, police and international and Afghan soldiers.
Afghanistan's inexperienced security forces are taking over responsibility for fighting the Taliban, but fears are growing that the country could tip into civil war after NATO military operations cease at the end of next year.
