The attack comes days before a disputed referendum that could extend President Pierre Nkurunziza's term. The Burundian government has blamed "terrorists" from neighboring Democratic Republic of Congo for the assault.
An armed group has killed 26 people in northwest Burundi, the security minister said on Saturday.
The security minister of the east African country, Alain Guillaume Bunyoni, told reporters that the attackers were "terrorists" from neighboring Democratic Republic of Congo.
He said 24 people were killed in their homes on Friday night and two others died of their wounds at a local hospital.
The minister gave no further details about the attack on the Ruhagarika community of the rural northwestern province of Cibitoke.
The attack comes just days before Burundians vote in a controversial referendum that could extend President Pierre Nkurunziza's term until 2034. It was not immediately clear if the attack was related.
Eyewitnesses told journalists that the attackers came around 10 p.m. local time (2200 CET) and attacked households and set houses ablaze.
Some victims were hacked with machetes and others were shot or burned alive.