Mozambican police have detained the head of an elite unit allegedly involved in the murder of a poll observer in the run-up to elections last month, the police said Wednesday.
Anastacio Matavele, 58, the head of a local election observation mission, was shot dead at the wheel of his car days before a general election marred by fraud allegations.
Mozambican police accused members of one of its elite units of staging the murder, which took place in the southeastern Gaza province -- a stronghold of President Filipe Nyusi's Frelimo party, which won a sweeping majority in the October 15 polls.
"The commander of the police special operations group in Gaza province was arrested yesterday (Tuesday) in connection with the criminal case," said police spokesman Orlando Mudumane.
Matavele's attackers were caught after colliding into another vehicle at full speed as they fled the scene.
Two died on the spot and two were seriously injured. A fifth managed to escape and is reportedly still missing.
National police identified them as members of the Gaza rapid intervention force.
They suspended the unit's provincial commander Tudelo Guirrugo and launched a commission of inquiry into the murder.
Gaza's provincial court issued Guirrugo's arrest warrant on Tuesday.
Mudumane said the case was in "preparatory stage" and that the investigation was still ongoing.
Mozambique saw one of its most violent campaigns ever with at least 10 people killed in the run-up to the election, according to a local observer mission.
Matavele was one of the victims, along with the Renamo Women's League leader, whose bullet-ridden body was found with her husband's in the western province of Tete.
The election has posed a major challenge to an already fragile peace agreement between Frelimo and its arch-enemy Renamo, a rebel group turned main opposition party.
Frelimo and Renamo fought a brutal civil war from 1975-1992 that left nearly one million people dead.
Fighting picked up again between 2013 and 2016, after which the two parties entered negotiations that culminated with a peace deal in August.
Renamo has accused the government of "massive electoral fraud" and of breaching the peace deal by using violence and intimidation on voting day.
Frelimo has denied the allegations.
Nyusi secured a second term with 73 percent of the vote, while Renamo's leader Ossufo Momade came second with under 22 percent.