Sources said the explosives were placed on a motorbike.
Herat provincial council member Mohammad Sardar Bahaduri confirmed the attack and said it was carried out by two Taliban fighters who had infiltrated the base.
In the last few months, Afghanistan has witnessed a surge in violence despite the ongoing intra-Afghan peace talks to resolve the conflict in the country.
The two sides held extensive conversations on issues of strategic mutual interest, including on synchronising efforts to combat terrorism and build peace
Shane Getkate has been added to Ireland's squad as a replacement for injured David Delany for the series against UAE and Afghanistan.
Tariq Arian, spokesman for the interior minister, said a spokesman for the ministry's public protection forces, a security force, was one of the three killed in the attack.
The ODI series between Afghanistan and Ireland is a part of the World Cup Super League series.
The insurgents have launched continuous attacks in several districts on the outskirts of the provincial capital Kandahar city, which still remains in the control of Afghan forces.
The stop-and-go talks come amid growing doubt over a U.S.-Taliban peace deal brokered by outgoing President Donald Trump.
The official said Taliban terrorists had assembled in these areas to plan attacks on security forces.
The attack unfolded at around 7 am local time and in Childokhtaran area along the Herat city-Turghundi highway.
Earlier, media quoted the local officials as saying that four members of public uprising forces, including their commander, were killed in a clash against the Taliban in Bati Kot district
The Afghan players haven't arrived yet as the Afghanistan Cricket Board hasn't announced the team and the players are yet to get a visa.
In mid-December, the National Directorate of Security officials conducted a major operation in Kabul, which resulted in the detention of about 10 Chinese intelligence agents.
The Taliban have halted their attacks on US and international forces but continue to target Afghan security forces even as the insurgents have held talks this year with the US-backed government.