Zimbabwean security forces confirmed Friday that soldiers and police fought on the streets of Harare earlier this week, as nationwide tensions grow under 93-year-old President Robert Mugabe.
Witnesses told local media about a hundred uniformed soldiers wielding batons and whips charged into a bus terminus on Tuesday night and beat up police officers, leaving many prostrate on the ground.
The violence, which underscores friction between the police and army, was reportedly triggered by police using spikes to deflate the tyres of a military vehicle after an alleged traffic offence.
"We want to categorically condemn that incident and assure the nation that a joint team has been set up to conduct comprehensive investigations," the police and defence forces said in a joint statement.
"We also want to reaffirm that as security forces we are fully united despite this incident," said the statement read out by police spokeswoman Charity Charamba, who declined to take questions from reporters.
One witness told the privately-owned Daily News that they saw soldiers "beating police officers ruthlessly".
The People's Democratic Party, a small opposition party, said the clash was a "sign of how dangerous our society has become."
Zimbabwe is set to hold elections next year when authoritarian leader Mugabe, who is increasingly frail, will likely hold onto power after ruling since independence in 1980.
The military and police have played a key role in suppressing dissent during his reign.
Zimbabweans face a daily struggle to get cash, standing in line for hours outside banks that often limit withdrawals to just $20.
The economy has halved in size since 2000, with millions emigrating to seek work.
Traffic police in the country frequently clash with civilians over the use of spiked iron bars to stop vehicles at roadblocks that cause long delays.
Drivers post videos on social media showing arguments with police officers, who often seek bribes.
One video that attracted many views last year showed a policeman using abusive language in an alteration at a roadblock with an airforce officer.