Harare - Zimbabweans have reacted with outrage online after the state revenue authority threatened to seize cars recently imported into the country if their owners could not prove they had paid enough tax on them.Under pressure to find new sources of revenue, ZIMRA announced in a statement on Tuesday that all owners of vehicles imported between January 2014 and July 2016 should go to their local tax office "to get confirmation of proper clearance and regularise the clearance if found not to be in accordance with the applicable laws".Car owners who don't do this before the end of September "risk having [their] motor vehicle seized wherever it is found", the statement said.Import duties on used cars were hiked in June last year. Zimbabweans rely heavily on used cars imported via South Africa, Walvis Bay in Namibia, and Tanzania.Local car assemblers Willowvale Mazda Motor Industries and Quest Motor Corporation are struggling: last week a Quest executive was quoted as saying, by the official Chronicle newspaper, that the firm's capacity utilisation was just 1%.The tax authority's own chief and five senior officials were themselves suspended in May over allegations they had benefited from a car import scam.Tweeted @cemambo of the Zimbabwe Broadcasting Corporation on Tuesday: "Implication is there were some serious under declarations/valuations so people have to own up & pay."Implication is there were some serious under declarations/valuations so people have to own up & pay https://t.co/250wLBgtNs— Clarkson Mambo (@cemambo) July 26, 2016Others were angry. "What I know is almost everyone will have to pay something for their car," wrote one Zimbabwean.Amid a worsening economic crisis, ZIMRA missed its revenue collection target for the second quarter of the year by three percent, the privately-owned Newsday reported.The payment of civil servants' salaries has been regularly delayed over the past few months. But soldiers have already begun receiving their salaries for July, state media reports. With Mugabe, 92, facing growing challenges to his more-than-three-decade-long hold on power, the authorities make sure the security forces are paid first.