Zimbabwean police on Monday fired tear gas in suburbs of the capital an attempt to disperse angry demonstrators who burned tires and threw stones to protest fuel price hikes.Protesters were undeterred, blocking some roads in Harare after the government's weekend decision to more than double the price of gasoline. Children in school uniform joined the protests as Zimbabwe is in its worst economic crisis in a decade.Police also fired tear gas at dozens of protesters in downtown Bulawayo, Zimbabwe's second-largest city, witnesses said. The city is a centre of opposition to the government.Many people in the streets directed their anger at President Emmerson Mnangagwa, who took power after longtime leader Robert Mugabe was forced to resign in November 2017 but has not delivered on promises to revive the economy."Mnangagwa has failed, he must go," one protester shouted. Others chanted opposition slogans and sang songs denouncing Mnangagwa, a former confidant of Mugabe who was elected as president in an election last year that the opposition said was rigged."He lied that our lives will improve, but things are getting worse by the day since he took over. Prices have been rising every day," said protester Judith Chamambo.Most businesses in the centre of Harare were closed. Some briefly opened but had closed by midday, asking workers to return home.Many had to walk because they could not afford prices charged by the few public transport vehicles on the road. Some schools also closed and asked pupils to go home.Police deployed in large numbers. The Zimbabwe Congress of Trade Unions, the country's biggest labour federation, has called for a three-day strike this week.Most clashes occurred in Harare's Mabvuku and Epworth suburbs, where residents barricaded roads and prevented public transport vehicles from operating. Some people threw stones at cars.Government spokesperson Nick Mangwana said the opposition, civic groups and some foreign organisations are trying to use the fuel shortages and price increases to topple the government.The main opposition MDC party, some non-governmental groups and prominent activist Evan Mawarire said they support the shutdown.VIDEO: Demonstrations erupt in the Zimbabwean capital of Harare to protest against the sharp rise in fuel prices ordered by the government, in the midst of a severe economic crisis pic.twitter.com/Zpq19yolDb— AFP news agency (@AFP) January 14, 2019Video: Cars at Makoni police station in Chitungwiza burnt. #shutdownZimbabwe#ZimShutDownpic.twitter.com/U1LMrb5mTv— Open Parly ZW (@OpenParlyZw) January 14, 2019Scenes from Luveve Road, Emagetsini. Police tried to disperse crowd but ran out of teargas and "ran away".Luveve still #shutdown as roads still barricaded. Situation tense, according to my source on the ground, my brother @Iamtherealdon #shutdownZimbabwe #Bulawayo pic.twitter.com/txeDkx2XCw— Thandekile Moyo (@Mamoxn) January 14, 2019Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook.